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A report by the Bioethics Advisory Committee of Singapore October 2025 October 2025 COPYRIGHT © 2025 Bioethics Advisory Committee of Singapore All rights reserved. The law stated is as of 1 April 2025.

CHAIR Emeritus Professor Lee Eng Hin Emeritus Professor, Department of Orthopaedic Surgery, National University of Singapore (NUS); and Emeritus Consultant, Division of Paediatric Orthopaedics, National University Hospital (NUH) CO-CHAIR Dr Chew Wei Leong Associate Director and Senior Principal Scientist, Genome Institute of Singapore, A*STAR; and Adjunct Assistant Professor, NUS

MEMBERS Emeritus Professor Roy Joseph Emeritus Consultant, Department of Neonatology, Khoo Teck Puat - National University Children’s Medical Institute, NUH; and Director of the Paediatric Ethics Program, Centre for Biomedical Ethics, Yong Loo Lin School of Medicine, NUS Associate Professor Lai Poh San Associate Professor, Department of Paediatrics, NUS; and Deputy Chairman, Institutional Biosafety Committee, NUS Associate Professor Lim Tit Meng Executive Director, OceanX Professor Vineeta Sinha Professor, Department of Sociology, Faculty of Arts and Social Sciences, NUS

Mr Tan Sze Yao Director, Legal Office, Ministry of Health (MOH), Singapore Ms Joyce Teo Senior Health Correspondent, The Straits Times Mr Gregory Vijayendran Senior Counsel and Partner, Rajah and Tann Singapore LLP Dr Voo Teck Chuan Head, Office of Ethics in Healthcare, SingHealth; and Advisory, SingHealth Duke-NUS Medical Humanities Institute Professor Tan Sor Hoon (until Jun 2023) Professor of Philosophy and Academic Director, School of Social Sciences, Singapore Management University (SMU) Ms Audrey Chiang Senior Partner, Dentons Rodyk & Davidson LLP

Associate Professor Mahesh Choolani Head and Senior Consultant, Department of Obstetrics & Gynaecology, Yong Loo Lin School of Medicine, NUS; Chief and Senior Consultant, Department of Obstetrics & Gynaecology, NUH; and Group Chief, Obstetrics & Gynaecology, National University Health System (NUHS) Professor Julian Savulescu Chen Su Lan Centennial Professor in Medical Ethics, NUS; Director, Centre for Biomedical Ethics, Yong Loo Lin School Medicine, NUS; and Uehiro Chair in Practical Ethics, University of Oxford, United Kingdom

Associate Professor Tan Meng How Associate Professor, School of Chemical and Biomedical Engineering, Nanyang Technological University (NTU) Clinical Associate Professor Tan Ee Shien Head and Senior Consultant, Genetics Service, Department of Paediatrics Medicine, Kandang Kerbau Women’s and Children’s Hospital; and Chief Innovation Officer, Precision Health Research, Singapore Dr G. Owen Schaefer Assistant Professor, Centre for Biomedical Ethics, Yong Loo Lin School of Medicine, NUS INTERNATIONAL ADVISOR Professor Kazuto Kato Professor, Department of Biomedical Ethics and Public Policy, Graduate School of Medicine, Osaka University, Japan

SECRETARIAT Adjunct Professor (Dr) Raymond Chua Swee Boon Deputy Director-General of Health, Health Regulation Group (DDGH(HReg)), MOH Ms Rachel Chen (until Mar 2025) Director, Regulatory Policy and Legislation Division (RPL), MOH Dr Tiong Wei Wei (until Nov 2024) Deputy Director, Biomedical Ethics Coordinating Office/Precision Medicine and Research Branch (DD(BECO/ PM&R)), RPL, MOH Dr Adrian Sim Senior Assistant Director (SAD(BECO/PM&R)), RPL, MOH Mr Louis Peter Hor Senior Manager (BECO), RPL, MOH Ms Nathira Shafeen Manager (BECO), RPL, MOH Ms Toh Si Min Senior Executive, RPL, MOH Ms Beatrice Lee Health Policy Analyst (PM&R), RPL, MOH

Ms Sharon Shen Executive (BECO), RPL, MOH Ms Muthusubramanian Shruti Executive (BECO), RPL, MOH Dr Durkeshwari Anbalagan-Raj (until Mar 2023) Senior Assistant Director (SAD(BECO/PM&R)), RPL, MOH Dr Phua Zheng Yen (Dec 2022 until Nov 2023) Research Fellow, NUS

PATRON Dr Tony Tan Keng Yam Honorary Patron and Distinguished Senior Fellow, SMU; and Former President of the Republic of Singapore EMERITUS ADVISOR Emeritus Professor Lim Pin Emeritus Consultant, Division of Endocrinology, NUH; and Emeritus Professor of Medicine, NUS CHAIR Emeritus Professor Lee Eng Hin Emeritus Professor, Department of Orthopaedic Surgery, NUS; and Emeritus Consultant, Division of Paediatric Orthopaedics, NUH DEPUTY CHAIRS Professor Kon Oi Lian Professor (retired), Duke-NUS Medical School Mr Gregory Vijayendran Senior Counsel and Partner, Rajah and Tann Singapore LLP

MEMBERS Dr Chew Wei Leong Associate Director and Senior Principal Scientist, Genome Institute of Singapore, A*STAR; and Adjunct Assistant Professor, NUS Professor Chin Jing Jih Deputy Group Chief Executive Officer (Clinical and Academic Development), National Healthcare Group; and Senior Consultant Geriatrician, Tan Tock Seng Hospital (TTSH) Emeritus Professor Roy Joseph Emeritus Consultant, Department of Neonatology, Khoo Teck Puat - National University Children’s Medical Institute, NUH; and Director of the Paediatric Ethics Program, Centre for Biomedical Ethics, Yong Loo Lin School of Medicine, NUS

Associate Professor Lai Poh San Associate Professor, Department of Paediatrics, NUS; and Deputy Chairman, Institutional Biosafety Committee, NUS Mr Charles Lim Aeng Cheng Principal Senior State Counsel, Legislation Division, Attorney-General’s Chambers Associate Professor Lim Tit Meng Executive Director, OceanX

Dr Nazirudin Bin Mohd Nasir Mufti, Office of the Mufti, Islamic Religious Council of Singapore (MUIS) Adjunct Professor Ngiam Kee Yuan Head, Academic Informatics Office, NUHS; Head and Senior Consultant, Division of General Surgery (Endocrine and Thyroid Surgery), Department of Surgery, NUH; Senior Consultant, Division of Surgical Oncology, NCIS; and Adjunct Professor, Department of Surgery, NUS Medicine Professor Vineeta Sinha Professor, Department of Sociology, Faculty of Arts and Social Sciences, NUS

Professor Patrick Tan Boon Ooi Dean-designate, Duke-NUS Medical School; Executive Director, PRECISE; and Chief Scientific Officer, Genome Institute of Singapore Mr Tan Sze Yao Director, Legal Office, MOH, Singapore Ms Joyce Teo Senior Health Correspondent, The Straits Times

Dr Voo Teck Chuan Head, Office of Ethics in Healthcare, SingHealth; and Advisor, SingHealth Duke-NUS Medical Humanities Institute Foreword vi Executive Summary 1 Chapter 1: Introduction 9 Chapter 2: Legislative And Regulatory Frameworks For HNGE 20 Chapter 3: General Ethical Principles In HNGE 31 Chapter 4: HNGE Techniques/Technologies And Their Relationship 37 With Gene And Cell Therapies Chapter 5: Potential Research And Clinical Applications Of HNGE 44 And Current Established Methods To Treat Diseases

Chapter 7: Safety And Long-Term Effects Of HNGE 62 Chapter 8: Procurement And Use Of Human Embryos And Oocytes 70 In HNGE Research Chapter 9: Equitable Access And Allocation Of Resources 76 Chapter 10: Genetic Enhancement And The Effects On Society 80 Chapter 11: Governance And Framework Tools For HNGE 88 Chapter 12: Conclusion 95 Chapter 13: Recommendations For Clinicians, Researchers, Research 101 Institutions, Regulatory Authorities, And Institutional Review Boards (IRBs) Glossary 112 Annexe A: Distribution List For Consultation Paper 117 Annexe B: Written Responses Received During The Public Consultation 124

Advances in Human Nuclear Genome Editing (HNGE) technology in recent years have resulted in the discovery of more precise tools that hold great promise in advancing both human biomedical research as well as clinical research. These tools allow us to alter genetic material, which can lead to promising breakthroughs in the treatment of genetic disorders, cancers, and infectious diseases. In biomedical research, HNGE technology can facilitate the study of gene function and disease mechanisms, and accelerate drug discovery and personalised medicine.

Techniques such as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) editing allow for precise modifications in the genome, enabling researchers to target specific genes associated with hereditary diseases. This unprecedented manipulation of genetic material offers the potential to eliminate certain health conditions, reduce susceptibility to various illnesses, and the overall improvement of human health. , non-heritable and heritable gene editing) and addresses the ethical, legal and social principles necessary to guide the responsible use of HNGE in biomedical research and clinical applications.

Amid a growing potential to modify the human genome for therapeutic purposes, some key ethical concerns have arisen, such as issues of consent, unintended consequences such as mosaicism and off-target effects, safety, accuracy and the potential for unforeseen health risks. Furthermore, the long-term effects of gene editing, especially across generations, for heritable gene editing, remain uncertain, thus necessitating rigorous research to ensure the safety and wellbeing of individuals in the future.

Another important ethical consideration pertains to the potential application of HNGE technology for genetic enhancement, which raises concerns about equitable access, unintended consequences and the shift in attitudes and behaviours towards reproductive choices. Therefore, it is imperative that these ethical issues be addressed, so as to promote safe, responsible and equitable advancements in HNGE.

Responsible and ethical use of HNGE technology is crucial as we explore ways to treat and prevent genetic diseases, improve health outcomes, and enhance human wellbeing. A ‘respect for persons’ is a foundational ethical principle in this area, emphasising the inherent dignity, autonomy and rights of individuals participating in biomedical research and clinical applications involving HNGE technology. Researchers and clinicians must demonstrate respect for individuals by ensuring that informed consent is obtained, particularly given the potential long-term and heritable effects of gene editing.

Alongside this is the principle of ‘proportionality’, which requires that the potential benefits of gene editing are carefully weighed against the risks, and that risks are minimised as much as possible. By adhering to these ethical principles, and others outlined in this report, researchers, clinicians, research and healthcare institutions can navigate the complex landscape of HNGE, make balanced and fair decisions and promote advancements that align with societal values and ethical standards.

The Bioethics Advisory Committee (BAC) extends its appreciation to all individuals and organisations for their valuable feedback during the public consultation process. In developing our recommendations, we have carefully reviewed all feedback received, and this report includes a thorough overview of the wide range of perspectives expressed. FOREWORD

Finally, I would like to thank the Review Group members, our International Expert and my fellow Committee members for their dedication and commitment to the detailed review of this complex topic. Their insights into the ethical, legal and social issues of HNGE, as well as their openness to diverse viewpoints during the consultation process, have been truly invaluable. I am confident that this report will serve as a useful resource and will provide guidance to academics, researchers, medical practitioners, healthcare professionals and policymakers in addressing ethical considerations around HNGE in their respective fields. Emeritus Professor Lee Eng Hin Chair Bioethics Advisory Committee 2025

1. This report addresses the ethical, legal and social issues arising from Human Nuclear Genome Editing (HNGE). It aims to guide academics, healthcare professionals, researchers, Institutional Review Boards (IRBs) and Clinical Ethics Committees (CECs) on the ethical use of HNGE technologies in biomedical research and clinical applications. A public consultation was conducted by the BAC from 6 June 2024 to 13 August 2024 to collate responses from both stakeholders and members of the public. This feedback has been reviewed and incorporated into the advisory report.

2. Legislation and guidelines play an important role in navigating the ethical, legal and social implications surrounding gene editing. It is important for clinicians, healthcare institutions, researchers and research institutions to adhere to relevant legislation and guidelines to ensure ethical and safe utilisation of gene editing technology. This chapter discusses the legislation and regulatory frameworks for HNGE in Singapore and other countries, as well as international guidelines on HNGE.

3. The principle of respect for persons refers to the autonomy of individuals making decisions related to biomedical research that involve gene editing or its clinical applications. The autonomy of an individual may be compromised if they are not fully informed of the possible benefits, risks and repercussions of research and clinical applications involving gene editing technologies. It is important to consider not only the autonomy of those put in a position of having to make decisions, but also the best interests of those with a diminished capacity, or even no capacity whatsoever, to give valid informed consent.

4. The principle of solidarity reflects the importance of altruism and other pro-social motives as a basis for participation in biomedical research. It also reflects the willingness and moral obligations of individuals to share the costs associated with scientific progress and participation in HNGE research, such as potential risks, in return for the common good.

5. The principle of justice requires that gene editing technology and therapy are accessible to the public. However, justice involves not only equitable access to HNGE technology but also addressing potential stigmas and promoting inclusive attitudes towards individuals with disabilities.

6. The principle of proportionality requires that the potential benefits to individuals and society in general, brought about by the editing of the human genome, should outweigh the anticipated risks of the research and clinical applications outlined above. The stringency of any regulation or governance framework developed for research employing gene editing, including a de facto prohibition of specific research activities, must be proportionate to the risks being mitigated. EXECUTIVE SUMMARY

7. The principle of sustainability is broadly understood to support arguments for the conservation of nature and the minimisation of resource depletion for the good of our planet. Therefore, research processes and outcomes involving HNGE technology should not unfairly jeopardise or prejudice the welfare of future generations.

8. The principle of inclusivity makes clear that the benefits of research and potential clinical applications of the technology are considered a public good and need to be accessible to everyone. It is important to carefully consider the knowledge and perspectives of HNGE as informed by different social, cultural, and religious beliefs, and to also work closely with the different groups of people to facilitate ‘community-engaged research’. Appropriate stakeholders such as patients, prospective parents and the wider public alike should be consulted and engaged to identify, prioritise and reach consensus on the specific areas, topics or questions that the research employing gene editing aims to address.

9. The principle of transparency highlights the ethical responsibility and moral and legal liability incumbent upon researchers and their institutions stemming from the decisions and actions that they take as a consequence of their research findings. HNGE research methods, analysis and data must be reported and disseminated openly, clearly, comprehensively and in a timely manner.

10. The principle of responsible stewardship of science requires that processes and outcomes of HNGE research be aligned with the values, needs and expectations of society, as identified from stakeholder engagement. This principle extends beyond the dissemination of information and requires taking the views of all stakeholders into consideration. HNGE Techniques/Technologies and their Relationship with Gene and Cell Therapies

11. This chapter provides an overview of the steps involved in gene editing, and discusses the different types of gene editing technologies used for HNGE research, and the relationship between gene editing, gene therapy and cell therapy. Potential Research and Clinical Applications of HNGE and Current Established Methods to Treat Diseases

12. This chapter discusses the potential research and clinical applications of HNGE, such as to understand diseases (e.g., the development of cancer), to understand the development of human embryos, diagnostics and drug discovery tools, to improve resistance to diseases, and to reduce predisposition to diseases. The chapter also discusses the current established methods to treat diseases, which include conventional treatments, prenatal testing, adoption, selective termination of pregnancy, embryo selection, the use of donated gametes and intrauterine foetal gene therapy. Mosaicism, Off-Target Effects, and On-Target Undesirable Modifications

13. Gene editing technology, when used in a controlled manner, can facilitate corrections to the genomic sequence to be achieved with precision, to rectify or remove mutations that might otherwise lead to unfavourable health conditions. However, such technology could also lead to unintended biological outcomes such as chromosomal mosaicism in embryos, and undesirable consequences arising from off-target mutations and deletions. This chapter discusses the ethical principles of proportionality, sustainability, solidarity, and responsible stewardship of science, the ethical issues of chromosomal mosaicism, off-target effects and on-target undesirable modifications, along with their impact on both individuals and society as a whole, which would be important considerations for potential applications of HNGE.

14. While gene editing offers new ways of treating diseases and may potentially be used for enhancement of human performance, its widespread use in clinical practice is yet to be readily accepted. This is because the technology is still in the early stages of its development, which raises concerns regarding the safety and long-term side effects of the technology on individuals who receive the treatment. The chapter discusses the ethical principles of proportionality, sustainability, and responsible stewardship of science, and the ethical issues of long-term side effects and consequences of non-heritable and heritable gene editing. It also discusses the management of these consequences through long-term follow-up and intergenerational monitoring of patients involved in potential interventions of HNGE by researchers and healthcare professionals.

Procurement and Use of Human Embryos and Oocytes in HNGE Research 15. Human embryos have been used by researchers in gene editing as a tool to enhance knowledge about human gene function and early embryonic development, as well as to advance research on infertility, genetic diseases and intractable diseases. While procuring oocytes with the desired genotype from healthy individuals can enable researchers to study gene mutations in oocytes for a given disease-causing gene, or to correct a specific gene mutation, it may lead to health risks for donors.

The chapter provides an overview of the 14-day limit for embryo research, the different types of embryos used in HNGE research, and discusses the ethical issues involved in the procurement and use of embryos and oocytes in gene editing research. These include health risks to donors and potential breaches of privacy and of the confidentiality of donors’ genomic data.

The chapter also discusses the relevant ethical principles of respect for persons, justice, proportionality, and transparency, which researchers and research institutions should consider to ensure that the autonomy and wellbeing of oocyte donors are respected, and to enhance transparency in the research process.

16. Gene editing technologies extend beyond discovering and developing therapies, particularly for rare genetic disorders, severe diseases such as cancer and treatment of infertility. These technologies can potentially be used for enhancing specific traits. However, as with many new modalities in medicine, gene editing technologies also give rise to concerns such as inequitable access by those who are in need but cannot afford them.

The chapter considers the potential issues arising from a lack of access to HNGE technologies for clinical applications due to high costs and under-representation of the Asian population in clinical data involving HNGE research. The chapter also discusses the applicable ethical principles of justice and inclusivity that researchers and research institutions should consider when seeking to improve gene editing for use in research and clinical applications, and in designing clinical trials for HNGE research. EXECUTIVE SUMMARY

17. Recent technological advances have given rise to the possibility of gene editing being used in applications that go beyond therapies and medical interventions, including genetic enhancement of physical attributes and cognitive abilities. However, such potential clinical applications of gene editing technologies can raise several ethical issues. The chapter discusses the ethical issues involved in the applications of gene editing technologies for genetic enhancement, including their unintended consequences, social inequity and the shift in attitudes and behaviours towards reproductive choices.

The chapter also discusses the relevant ethical principles of proportionality, sustainability, justice, inclusivity, transparency and responsible stewardship of science that researchers, research institutions and IRBs should consider in the applications of gene editing technologies for enhancement if permitted in the future.

18. As with other technological advances, gene editing raises ethical and social issues that must be addressed by having proper governance frameworks in place. The chapter discusses the governance and regulatory frameworks for HNGE at various levels: (i) institutional research level; (ii) clinical trial level; and (iii) national level. The chapter also discusses the different tools and approaches to strengthening existing research governance frameworks, which include (i) professional self-regulation; (ii) providing education and training on HNGE for researchers and clinicians; (iii) reinforcement of institutional practices; (iv) setting up of HNGE registries; (v) whistleblowing mechanisms; and (vi) other international mechanisms for reporting unethical HNGE experiments. Recommendations (see Chapter 13 for the detailed recommendations)

19. The BAC recommends that researchers and research institutions should put in place an oversight mechanism to ensure HNGE activities are conducted appropriately. The BAC also highlights the need to ensure that there are clear and well-established protocols and processes for oversight and review, so as to ensure that HNGE research is conducted in an ethical manner.

20. Researchers and research institutions should set research priorities based on the needs of society and develop strategies to prevent or reduce the occurrence of errors that are known to arise from HNGE. 21. Clinicians should consider current established intervention methods to treat or prevent diseases among individuals and their offspring until the safety and efficacy of HNGE technologies are clear. Non-Heritable Gene Editing (for Research and Clinical Applications)

22. Researchers, research institutions and clinicians should achieve a favourable riskbenefit ratio for patients undergoing clinical trials or clinical interventions involving nonheritable gene editing. 23. Governments, regulatory bodies and IRBs should establish an evaluation framework at the institutional level (i.e., guidelines and oversight committees) to assess the benefits of gene editing technologies in relation to its risks, such as off-target effects, the types of tissues affected, unintended genetic changes and the potential for immune responses.

24. Researchers, research institutions and clinicians alike should ensure that patients undergoing gene editing interventions or HNGE clinical trials have a sufficient understanding of the intervention and that they are made fully aware of the potential risks and complications prior to receiving treatment. Patients’ informed consent and IRB approval are to be obtained prior to the procedure.

25. Regulatory bodies should establish guidelines on the required information that should be covered in informed consent for researchers and research institutions to refer to. This is to ensure that all relevant information on the gene editing intervention is made known to the patient or participant.

26. Researchers and clinicians who are involved in research and clinical applications involving HNGE technologies should be appropriately trained, so as to be able to accurately assess the potential benefits and risks of gene editing interventions and conduct appropriate counselling for patients, as well as ensuring that those same patients are able to give consent that is entirely informed.

27. Researchers, research institutions and clinicians should ensure that the risks of any unintended consequences from non-heritable gene editing interventions becoming heritable are avoided as far as possible, and that these risks are documented and assessed appropriately.

28. Researchers, research institutions, and clinicians should continuously review whether existing regulations and guidelines are adequate in terms of managing the risks and benefits of HNGE. 29. Researchers and physicians should perform long-term follow-ups on patients and participants in clinical trials evaluating new therapeutic modalities for non-heritable gene editing, to help mitigate the risk of any delayed adverse event due to the treatment.

30. Public agencies, researchers, academics and the government, should consider implementing health-economic analyses and models of funding to ensure that HNGE technology is affordable for all individuals with a corresponding medical need. Recommendations for Gene Editing on Germline Cells or Embryos for Basic Research

31. The BAC does not recommend culturing human embryos whose genes have been edited beyond 14 days. It has asserted that the creation of human embryos solely for research purposes can only be justified when there is strong scientific merit and potential benefit from such research.

32. Researchers and research institutions should ensure that consent for the donation of surplus oocytes or embryos is kept separate from the consent of treatment for women undergoing fertility treatments. EXECUTIVE SUMMARY 33. Research institutions should establish an independent panel to interview women who intend to donate eggs specifically for research (i.e., those who are not undergoing fertility treatment).

34. Researchers should ensure that women are fully informed of the risks involved in gene editing and are given sufficient time to give consent prior to undergoing oocyte procurement procedures for gene editing research. 35. Researchers and research institutions should implement safeguards to protect oocyte donors and ensure that there is no coercion or undue influence in their decision to donate.

36. The relevant regulatory authority should consider setting a limit on the amount of compensation under Section 13 of Singapore’s Human Cloning and Other Prohibited Practices Act to avoid any inducement. 37. Researchers should only consider using surplus embryos created through assisted reproduction treatment for HNGE research if the risks of procuring oocytes solely for such research outweighs the benefits. Recommendations for Heritable Gene Editing for Clinical Research and Clinical Applications

38. The BAC does not recommend heritable gene editing for clinical research and applications until the safety and efficacy of such technology can be validated, as its long-term outcomes remain unknown. 39. Researchers and research institutions should conduct more research to develop methods to mitigate off-target effects and other unintended mutations from heritable gene editing on human embryos, so long as the safety of gene-editing established pregnancy is yet to be established.

40. If heritable gene editing for clinical research is deemed safe enough and permitted in the future, researchers and research institutions should conduct intergenerational monitoring which could help researchers determine the long-term side effects of heritable gene editing on an individual that might be passed on to future generations, and assess its safety and efficacy for clinical use. Recommendations for Non-Heritable and Heritable Gene Editing for Genetic Enhancement

41. Researchers should weigh the benefits against the risks of applications of gene editing for enhancing physical attributes or cognitive abilities if genetic enhancement is permitted in the future. 42. Researchers and clinicians should review the need to limit the applications of gene editing technologies for enhancement to cases where they do not result in unfair advantage or disadvantage to certain individuals.

43. Governments, funding agencies and IRBs should implement oversight measures to ensure that the use of gene editing technologies adheres to the principle of justice. 44. Researchers, scientists and the government should engage with the views and shared experiences of people living with the conditions that are targeted for HNGE intervention, and ensure that their viewpoints are considered in shaping policies that reflect the needs and concerns of affected communities.

45. Regulatory authorities and IRBs should conduct more studies to assess the societal impact of permitting genetic enhancement in terms of potential increased vulnerability of particular populations to risks of harm and discrimination, and create frameworks and regulations to prevent discrimination. In addition, they should create policies to ensure equitable access to gene editing technology to reduce potential disparities in access and use.

46. Scientists, research institutions, clinicians, medical institutions and approving authorities must ensure that reporting mechanisms are in place to prevent the misuse or abuse of gene editing technologies for enhancement. Governance of Research and Clinical Applications Involving HNGE

47. Research institutions should review institutional policies and practices at regular intervals in order to manage the risks and maximise the potential benefits that may arise from HNGE research. They should also consider the views of the public, patients or others with a vested interest in the activities conducted by such institutions.

48. Regulatory bodies, government organisations and funding agencies that are developing internal standard operating procedures (SOPs) for HNGE research or clinical trials should be encouraged to implement guidelines and establish robust systems to understand, monitor and minimise or mitigate the relevant risks and their impact on research subjects and patients undergoing clinical trials.

49. Governments and policy makers should constantly review and update laws and guidelines pertaining to applications and research involving HNGE. Tools and Approaches to Strengthen Existing Research Governance 50. There should be professional self-regulation within the scientific community so that scientists conducting HNGE research are responsible and accountable to their peers and society as a whole.

51. Academic, research and healthcare institutions should develop educational training or ethics modules specific to HNGE for graduates who are looking to pursue research in gene editing or professions engaged in clinical applications of HNGE. 52. Research and healthcare institutions should continually review existing IRB ethics review processes and develop SOPs for HNGE research, which should be regularly revised and kept up to date with the developments in HNGE research, technologies and legislation.

53. The BAC recommends the setting up of national registries to track and monitor research and clinical trials involving HNGE to allow easy access of HNGE research and clinical trials information to relevant stakeholders. EXECUTIVE SUMMARY 54. Research institutions or governments should introduce whistleblowing mechanisms at an institutional or national level to establish effective reporting channels and help maintain comprehensive protection and support for those who report illegal, unregistered, unethical or unsafe HNGE research. Governance Framework for Heritable Gene Editing and Gene Editing in Embryos or Germline Cells for Research Purposes

55. Research institutions and relevant regulatory authorities should ensure that the extent of oversight in developing governance and framework tools is commensurate with the extent of ethical, social and health risks involved, whether for clinical research and clinical applications of heritable gene editing, or the basic research activities of gene editing in embryos or germline cells.

1). As the cells in the body replicate, genetic mutations/changes in the nucleotide sequences of the DNA may take place, which can lead to changes in protein structure and cell function. Genetic mutations such as these could lead either to genetic conditions such as cancer, or they could help humans better adapt to their environment over time. Gene editing offers the potential to treat genetic diseases caused by such genetic mutations. 1).

Gene editing tools allow for a harmful DNA variant to be edited to a healthy variant—one that could potentially prevent or cure a genetic disease, hence representing great potential for breakthroughs in medical treatments. Therefore, researchers have shown great enthusiasm for new technologies in therapeutic gene editing over the years. Figure 1.1: Diagram portraying the Relationship between Genes, Genomes, DNA, Nucleotides and the Role of Gene Editing

1.2 Scientists use different technologies to edit DNA where these technologies act like scissors, cutting the DNA at a specific spot before removing, adding or replacing the DNA where it was cut. The first attempts at gene editing occurred in the 1980’s, since which time many researchers have tried to develop methods to edit a specific gene.

Genes DNA Nucleotides Cell Genome Chromosome Gene editing: Changing the DNA sequences (A, T, C, G) on the genome. INTRODUCTION New genomic tools have made it easier than ever to edit DNA, where they have enabled DNA to be edited in a simpler, faster, cheaper, and more accurate manner, such that the desired outcome is achieved with minimal off-target effects. Gene editing tools also have the potential to broaden scientists’ knowledge of genetics by generating cellular models, which can mimic various human diseases to help better understand disease consequences and develop new treatments.

1.3 HNGE may be broadly classified into: (a) non-heritable gene editing; (b) heritable gene editing for clinical research and applications; and (c) gene editing in embryos or germline cells for research. a. Non-heritable (or somatic) gene editing is carried out in cells that cannot, or do not contribute to, gamete formation, which is responsible for the generation of reproductive cells. As such, changes made to these cells cannot be inherited by the offspring of the individual receiving the treatment. Common applications of nonheritable gene editing include clinical treatment of genetic disorders in individuals with cystic fibrosis and severe combined immunodeficiency (SCID) syndrome, or, more broadly, for research purposes.

b. Heritable gene editing refers to genetic modifications made to gametes (eggs or sperms), germline cells or early-stage embryos, which can be applied in both clinical research and clinical applications (if permitted in the future): i. Clinical research involving heritable gene editing involves interventions with human subjects to study the safety, efficacy and ethical considerations of editing genes that can be inherited by future generations.

For example, editing germline cells or embryos to correct disease-causing mutations that are subsequently transferred into the research subject raises the risk that the patient’s future off spring might inherit these modifications. Typically, this includes clinical trials in controlled environments, often with stringent regulations and oversight, to explore potential therapeutic benefits and address possible risks. Clinical research is exploratory and is not intended for routine clinical practice. ii.

Clinical applications of heritable gene editing refer to the potential use of heritable gene editing techniques in clinical practice, where alterations are made to (i) genomic DNA in gametes; or (ii) any cells that give rise to gametes, including the single cell zygote resulting from fertilisation of an egg by a sperm cell, or cells of an early embryo, leading to the transfer of the resultant embryo to a woman’s uterus to initiate a pregnancy that could result in the birth of a child with a modified genome.

When the child reaches the age capable of producing gametes, such genetic edits made to these cells will be inherited by the progeny and passed down to future generations. Heritable gene editing can potentially be used in clinical applications for the purposes of treatment of diseases, conferring resistance against diseases, treatment of infertility, and the enhancement of traits (if permitted in the future). c. Gene editing may also be applied on germline cells or embryos for basic research, which does not involve interventions with human subjects.

It can be used in reproductive medicine to correct mutations in germ cells in testes or ovaries, or in germ cells used to derive gametes in vitro for studies involving cellular development or to improve understanding of genetic diseases. Progenitor cells of gametes can also be isolated and genetically modified in vitro but are not implanted into a human body to establish pregnancy.

For instance, missense mutations in regulator genes in oocytes, which may impede oocyte maturation or early embryonic developmental arrest and lead to failure of fertilisation, may be corrected to recover the oocytes’ developmental potential and raise chances of successful pregnancy. In azoospermia patients who suffer from a chromosomal mutation that causes meiotic arrest of sperm cells, spermatogonial stem cells (SSC) may also be genetically corrected in infertile males.

However, this investigative therapy is currently in its experimental phase with further studies needed to warrant any translational applications, as changes that are theoretically present in the germ cells can potentially be passed on. II. Global and Local Trends on the Use of HNGE in Human Biomedical Research and Clinical Applications

4 Overtheyears,geneeditinghaswitnessedaparadigmshiftwiththeadventoftechniques in gene editing involving the clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 (CRISPR-Cas9), zinc-finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs). These enzymatic tools share a common characteristic of changing the DNA sequences within the genome by leveraging a combination of programmable targeting of specific sites, inducing DNA breaks, inserting DNA, deleting DNA, modifying the chemical identity of nucleotides and/or harnessing the endogenous repair mechanism within the cell.

Such changes can repair gene mutations associated with disease. Further advancements in gene editing methods have also enhanced our knowledge of human genetics, epigenetics, molecular biology and pathology, enabling disease modelling and allowing drug discovery to be made more viable. As such, gene editing-mediated trials have led to positive treatment outcomes in patients with haematological disorders, such as sickle cell disease and thalassaemia.

Nonetheless, as the sample sizes in these trials were small, and follow-up duration could be short, a larger sample size and long-term follow-up would be required to accurately assess the long-term effects and sustainability of outcomes. INTRODUCTION

5 Moreover, the increasing prevalence of infectious diseases, cancer and genetic disorders have bolstered the advancement of medical science, which is also being driven by the demand for personalised medicine. However, personalised treatments require a thorough understanding of the factors contributing to the health and disease of that individual. The necessary process includes analysing the molecular dynamics of the cell at the genetic level to diagnose the status of disease, as well as predicting treatment outcomes from biomarkers.

For example, CRISPR in particular, but other gene-editing tools too, have demonstrated promise in repairing defective genes found in patients with severe diseases ranging from acquired cancer to inherited genetic diseases. The growth of the gene editing market is also driven by the increase in funding and initiatives by the government to develop complementary markets in vaccines, medical technologies, drugs as well as devices.

1.6 Currently, non-heritable gene editing is being explored via human biomedical research and clinical applications for a wide range of diseases from HIV to muscular dystrophy and even coronavirus disease 2019 (COVID-19). Gene editing in embryos or germline cells is also carried out through properly regulated research. The outcome may hold promise for the treatment and prevention of more complex diseases. Heritable gene editing in clinical research and clinical application, on the other hand, are strictly prohibited in most countries, including Canada, Australia, and across Europe, where any form of research involving germline gene editing is banned.

7 The gene editing market is dominated by North America due to the strong growth trend in the continent’s pharmaceutical and biotechnology industries, technological innovation in gene editing technology, increasing product approvals, as well as the rising number of clinical trials conducted for gene editing. For example, in March 2021, scientists at the University of California (UC) San Francisco, UC Berkeley, and UC Los Angeles received approval from the United States Food and Drug Administration (FDA) to jointly launch an early phase, first-in-human clinical trial of a gene correction therapy in patients with sickle cell disease using patients’ blood-forming stem cells.

The trial combined CRISPR technology developed at the Innovative Genomics Institute (IGI), which was founded by Nobel Laureate Jennifer Doudna, and experts at UCSF Benioff Children’s Hospital Oakland in cord blood and marrow transplantation, and in gene therapy for sickle cell disease.

1.8 In Europe, the United Kingdom (UK) has been contributing significantly to the growth of the gene editing market due to the nation’s growing elderly population and the increasing incidence of chronic diseases. The use of gene editing to treat children with severe diseases such as cystic fibrosis, muscular dystrophy and Tay-Sachs has also received great support based on the results from surveys conducted. While it remains illegal to edit embryonic genomes meant for pregnancies, younger generations are more open to the idea of designer babies suggesting that the ban could be lifted if it is proved that the procedure can safely prevent severe diseases.

1.9 There has been exponential growth in the gene editing market in the Asia Pacific region due to this vast region’s rising elderly population, the modernisation of healthcare practices, technological advancements and government initiatives to control diseases. For instance, in March 2021, scientists from the Genome Institute of Singapore (GIS) developed a novel CRISPR-based gene editor, a C-to-G base editor (CGBE), to correct mutations that lead to genetic disorders. CGBE is a CRISPR-based gene editor which allows substitution of a single base in faulty genomic sequences that are responsible for diseases such as cystic fibrosis, cardiovascular diseases, musculoskeletal diseases and neurological disorders. III. Advantages and Disadvantages of Non-Heritable Gene Editing, Heritable Gene Editing and Gene Editing in Embryos or Germline Cells for Research Purposes

a. Advantages and Disadvantages of Non-Heritable Gene Editing 1.10 Non-heritable gene editing offers the primary advantage of delivering new treatments or cures for diseases by changing disease-causing genetic mutations solely within somatic cells. This reduces the risk of propagating, particularly potentially detrimental, edit-related changes to future generations. However, the high costs of subscribing to non-heritable gene editing as a therapy may prove unaffordable and inaccessible to many.

1.11 In addition, when gene editing is performed inaccurately, the off-target effects can result in unintended edits, which is an important risk to consider. Unintended edits (mutations) may occur in a subset of cells during gene editing. When these groups of cells include important genes, such mutations could lead to harmful effects such as cancer. However, the probability of off-target effects varies according to the design of the gene editing technology and is often quantified with stringent genomic sequencing. Hence, off-target effects are an important factor to consider when weighing the benefits and risks of each gene editing treatment.

1.12 Non-heritable gene editing may exhibit a lower editing efficiency and less therapeutic outcome when compared to heritable gene editing. This is because while heritable gene editing ensures that all cells of future offspring inherit the edited genomic sequence(s), non-heritable gene editing often results in genetic mosaicism, where only a fraction of the cells is edited with the desired sequences, while the other remaining cells are unedited or unintentionally edited. This could lead to a non-homogeneous population of cells, which may be insufficient in eliciting the desired treatment response. Ongoing advances in more efficient and precise gene editing technology could enhance the efficacy of non-heritable gene editing. b. Advantages and Disadvantages of Heritable Gene Editing for Clinical Research and Applications

1.13 Heritable gene editing used for clinical research and applications could enable the correction of disease-causing mutations to be passed on from generation to generation INTRODUCTION and so prevent the disease from developing in subsequent generations. Such applications could also enable conferring resistance or enhancing traits that are inheritable in future generations. However, unintended edits introduced during genetic modifications may similarly be passed down to future generations, thus introducing potential negative effects to offspring. For instance, off-target effects, due to DNA double strand breaks at the wrong sites because of imprecise edits, have been reported in human zygotes. As with non-heritable gene editing, genetic mosaicism was observed in the same study too.

This calls for greater caution and the need for further research aimed at meeting existing risk/benefit standards for the approval of clinical trials and clinical applications of heritable gene editing. Further, approvals are given only for compelling reasons and under strict oversight (discussed in Chapters 6 and 7). The cost of receiving germline gene editing therapy may also be high, given the sophisticated technology involved, and therefore becomes unaffordable and inaccessible for many, potentially aggravating issues arising from societal inequality (discussed in Chapter 10).

1.14 Heritable gene editing for clinical research and applications may also be used to enable pregnancy by correcting mutations in germ cells, such as oocytes and spermatogonial cells, to potentially treat male and female infertility. This would allow parents with inherent fertility challenges to have their own children without receiving gametes from others, which would pose possible legal implications pertaining to the custodial rights of the child born (discussed in Chapter 5). Nonetheless, when mutations are introduced at the wrong site of the DNA in germline cells during the process of germline gene editing, such errors introduced in editing could possibly lead to unknown ramifications with severe consequences, adversely affecting individuals receiving the treatment as well as their future progeny.

c. Advantages and Disadvantages of Gene Editing in Embryos or Germline Cells for Research Purposes 15 Gene editing carried out in embryos or germline cells for basic research allows researchers to advance scientific research, including clinical research and clinical applications involving heritable gene editing, and to promote the understanding of human embryonic development. However, the procurement of human embryos for research purposes would be difficult due to risks involved for the donor. Furthermore, human embryos could be destroyed during or after use for research, raising ethical dilemmas, includingnon-maleficenceand concerns pertaining tojustice.

To ensure that germline gene editing research is conducted ethically, the BAC adopts the following positions: (i) specific and personal consent from the donors must be obtained before any oocytes or embryos are used for research; (ii) potential donors should be provided with sufficient information and time to make an informed decision; (iii) for women undergoing fertility treatment, consent for donation of surplus oocytes or embryos should be separate from the consent of treatment; (iv) the treating physician should not also be the researcher seeking consent for the donation of eggs and embryos for research;

and (v) as the process for donating eggs for research is time-consuming, invasive and associated with a certain degree of discomfort and risk, women who wish to donate eggs specifically for research must be interviewed by an independent panel. The panel must be satisfied that the individual is of sound mind, clearly understands the nature and consequences of the donation, and has freely given their explicit consent, without any inducement, coercion or undue influence.

16 Clinical research and clinical applications of both non-heritable and heritable gene editing, and gene editing in embryos or germline cells for research, should be properly and carefully assessed prior to approval, due to the known and unknown risks of gene editing technology. A known risk is off-targeting, where unintended edits can occur in genes. However, as with any new and evolving technology, there may be unforeseen risks that only become apparent over time. It can take many years to fully determine the spectrum of risks associated with gene editing.

Clinical studies are one of the key ways intended to uncover these potential long-term and unforeseen effects. Therefore, with technological advancements, continual evaluation is crucial to ensure a well-informed risk-benefit consideration. Such risk-benefit consideration may allow for the research and clinical applications of non-heritable gene editing to be conducted, if the benefits of the therapy outweigh the risks as well as other possible negative consequences that may arise from unintended mutations.

17 Nonetheless, heritable gene editing for clinical research and clinical applications for the purposes of treatment of diseases, conferring resistance, or the enhancement of traits, should not be recommended until safety and efficacy are well established and long-term effects are understood. This is because the mutations can be passed down to the future generations, and the unknown negative effects that could arise because of the errors in editing could outweigh the possible benefits of the therapy.

This is especially relevant if the technology is used to confer resistance to diseases or enhance certain traits which might expose future generations to harm. Most jurisdictions and international bodies such as the World Health Organization (WHO), and scientific and professional societies such as the International Society for Stem Cell Research (ISSCR), either recommend changes in policy and practice to support the reporting of possible heritable gene editing or do not recommend the use of heritable gene editing.

1.18 Heritable gene editing for clinical research and clinical applications for the purpose of treating infertility should be prohibited until the safety, efficacy and long-term effects are well established. This is because ooplasmic transfer and pronuclear transfer have only been practised for treating intractable infertility in some countries such as the UK, to prevent the inheritance of pathogenic mitochondrial DNA mutations in offspring. Furthermore, off-target effects arising from heritable gene editing can affect future progeny and could also harm the individuals undergoing the treatment when modifications to the genome are made at the wrong site.

1.19 However, gene editing in embryos or germline cells for basic research may be allowed if the research on human embryos is conducted before the 14th day of their creation. INTRODUCTION This practice is uniformly regulated across countries given that the embryos were a collection of cells shown to sustain in vitro for 12-13 days after fertilisation for research purposes. The Warnock Committee’s stand was premised on the view that only after the 14th day would the embryo be considered as an individual and, therefore, a person with rights to life. IV. Ethical Issues Arising from Heritable Gene Editing and Human Embryo Research

20 Heritable gene editing could result in inaccurate editing such as off-target effects and genetic mosaicism, both of which could result in the increased risk of heritable genetic diseases for future progeny. As such, the welfare of future offspring or children may be jeopardised (principle of sustainability) and further complications for the mother-to-be, such as psychological distress and infertility (principle of non-maleficence) may also arise.

There is also a lack of sufficient preclinical studies and clinical trials demonstrating the safety and efficacy of heritable gene editing (principles of beneficence, non-maleficence, and responsible stewardship of science) given the relative infancy of the technology. The difficulty in predicting potential harmful side-effects that could occur because of heritable gene editing and possible interactions of such resultant genetic changes with other genes or the environment, could render future offspring susceptible to unknown long-term side-effects.

These genetic alterations may continue to occur and be introduced to the population, which might then be difficult to ameliorate (principle of sustainability). 1.21 Extending the duration in which human embryos whose genes have been edited are cultured (i.e., beyond 14 days) could facilitate further development of heritable gene editing, but potentially risk leading to their misuse (principle of justice). Oocyte procurement for gene editing in embryos or germline cells for research is also physically invasive and could, therefore, pose significant risks to the health or life of the donor (principle of non-maleficence).

1.22 Furthermore, heritable gene editing for enhancement could exacerbate social inequities, resulting in skewed societal expectations of abilities and traits that are considered ideal, as well as aggravate inequitable access to germline gene therapy. As a result, the technology may be used by consumers in a coercive environment, such as that under societal pressure (principles of justice and sustainability). The general ethical principles of HNGE will be discussed in Chapter 3. V. Issues that could Arise when Ethics is not Incorporated into the Conduct of Human Biomedical Research/Clinical Applications Involving HNGE

1.23 The CRISPR babies scandal represents the most high-profile case of heritable gene editing in human embryos, in terms of the strong criticism that it drew from scientific and medical communities. In 2018, Chinese scientist He Jiankui applied germline gene editing to several human embryos resulting in the birth of two genetically modified babies. In doing so, He flouted established norms for safety and human protection. Claiming that his aim was to introduce the rare ability to resist infection from HIV, He sought to reproduce the phenotype of a specific mutation in the gene CCR5. However, He generated a frameshift mutation intended to make the CCR5 protein entirely nonfunctional instead of introducing the known mutation.

1.24 He Jiankui’s CRISPR experiment has attracted not only widespread attention but also controversy, which could shape research involving gene editing in humans for years to come, such as: a. Increased interest in research studies on non-heritable gene editing as scientists become cautious about conducting research in gene editing on germline cells; b. Further tightening of regulations and guidelines on gene editing in germline cells (and incidentally, non-heritable gene editing) due to additional caution practised by the scientific community, which could stifle developments in HNGE; and c. Adversely impacting the growth of gene editing in germline cells for research such as the number of researchers working in the field, research output and funding, despite the benefits that may be harnessed from such research if conducted ethically.

25 Following He Jiankui’s CRISPR baby scandal, there were several instances of similar studies involving gene editing carried out on germline cells or human embryos that triggered warnings from bioethicists. For example, several groups in China and the United States of America (US) published results of similar experiments in those ensuing two years, which went from using non-viable embryos to using ones that could conceivably be implanted. Separately, a study conducted in the US in 2017 verified the gene editing ability of CRISPR-Cas9 to correct mutations associated with genetic diseases using human embryos.

While research carried out in this area have underlined the need for caution, scientists nevertheless anticipate clinical applications as a feasible outcome arising from these studies. Therefore, it is important to carefully consider the ethical, social and legal implications involved in gene editing, and to put in place regulatory tools and a governance framework to prevent subsequent research from being carried out unethically.

1.26 Besides ethical issues and considerations, there are other challenges ahead, particularly in the clinical translation of heritable gene editing, where it is often difficult to delineate clinical applications from clinical research. An established clinical translation pathway for new therapies (i.e., a multistage controlled trial system to determine the safety and efficacy of a tested treatment) is not applicable to heritable gene editing, as INTRODUCTION

clinical trials involving heritable gene editing cannot be considered a controlled study design, given the absence of suitable controls for comparison. , phase zero or phase one) that involve microdosing of a new drug in a small number of patients to establish their safety, would be unsuitable for heritable gene editing studies. In standard first-in-human trials, an administered drug can be withdrawn instantaneously upon the discovery of adverse effects, and, if necessary, it might be possible to dispense treatments to counter such adverse effects.

However, these are not options for clinical trials involving heritable gene editing, as the intervention cannot be reversed when a genetically modified embryo has been implanted into the uterus. Given that the ethical issues arising from clinical research involving heritable gene editing would be similar to the ethical issues and considerations arising from clinical applications of heritable gene editing, any discussions on the ethical issues arising from heritable gene editing in this report apply to both clinical research and clinical applications, unless otherwise stated.

VII. Overview of Legislations and Regulatory Frameworks Governing HNGE 27 Most countries have enacted legislation that prohibits the use of heritable gene editing, such as Australia, Germany, and South Korea, while others such as the UK, the US, Japan and Singapore, have allowed the conditional use of gene editing in embryos or germline cells, namely for research purposes and with strict regulations. For instance, Australia’s ‘Prohibition of Human Cloning for Reproduction Act (2002, as amended 2017)’ prohibits heritable alterations to the genome.

Germany’s ‘Embryo Protection Act (1990, as amended 2011)’ has outlawed artificially altering the genetic information of a human germline cell as well as using a human germ cell with artificially modified genetic information for fertilisation. Authorities in Japan have also issued guidelines to restrict the use of human-fertilised embryos for basic research employing gene editing. While Singapore has yet to enact any specific legislation on gene editing, its ‘No.

S 622 Human Biomedical Research (Restricted Research) Regulations 2017’ states that every research institution and researcher conducting restricted research must ensure that such research carried out does not involve a human embryo which is more than 14 days old from the time of its creation (excluding any period when the development of the embryo is suspended). The Regulations also state that the research institution and the researcher must ensure that only surplus embryos created in assisted reproduction treatment may be used for research.

1.28 Most international guidelines recommend against the use of illegal and unsafe heritable gene editing. For instance, the WHO Expert Advisory Committee on Developing Global Standards for Governance and Oversight of Human Genome Editing issued new advisory guidelines in 2021 which recommend changes in policy and practice to support the reporting of possible illegal, unregistered, unethical, or unsafe non-heritable gene editing, heritable gene editing and gene editing in embryos or germline cells for research.

29 Most scientific and professional societies do not recommend the clinical use of heritable gene editing but do allow gene editing in embryos or germline cells for research. The International Society for Stem Cell Research (ISSCR) Guidelines (2021) do not recommend that heritable gene editing should be pursued at this time, as existing approaches are deemed unsafe or raise unresolved ethical issues. Additionally, they recommend that gene editing in embryos or germline cells for research should be allowed only after review and approval through a specialised scientific and ethics review process. International medical bodies such as the World Medical Association (WMA) issued a statement on human gene editing in which it opined that non-heritable gene editing should be implemented according to appropriate evidence that is collected via well-conducted and ethically approved research studies.

1.30 To address the emerging ethical, legal and social implications of HNGE in biomedical research, the BAC has published an advisory report and recommendations to guide researchers, academics, healthcare professionals, Institutional Review Boards (IRBs) and other ethics committees such as the Clinical Ethics Committees (CECs) on the ethical use of HNGE in biomedical research. While there are other pre-existing reports from the WHO and other global organisations or committees on this topic, the HNGE advisory report serves to guide the national ethical framework for HNGE in Singapore and provide the BAC’s recommendations to inform the Singapore government on its policy decisions. The advisory report also serves as a useful reference for local and overseas bioethics counterparts to understand Singapore’s position on HNGE. LEGISLATIVE AND REGULATORY FRAMEWORKS FOR HNGE

1 A complex landscape of legislation and guidelines has emerged in the realm of gene editing, aimed at navigating the ethical, legal, and social implications of its associated technologies. These regulatory measures seek to balance the potential benefits of gene editing with concerns surrounding safety, informed consent and equity. The first part of this chapter provides an overview of the legislation pertaining to HNGE, including those for (i) non-heritable gene editing for research and clinical applications, and (ii) heritable gene editing for both clinical research and clinical applications, as well as gene editing in embryos and germline cells for research.

The second part of this chapter provides an overview of the guidelines available to oversee the ethical applications of HNGE and discusses the different guidelines that (i) explicitly recommend against heritable gene editing for clinical applications, and (ii) recommend heritable gene editing for clinical applications based on certain conditions.

i. Non-Heritable Gene Editing (for research and clinical applications) 2.2 Non-heritable gene editing is generally allowed for research purposes in Singapore though approval is required from the Institutional Review Boards (IRBs) while detailed and informed consent needs to be obtained from participants. The use of gene editing products for innovative salvage therapy, which is the offering of an untested practice when conventional therapy has proven to be unhelpful in desperate or dire circumstances, is also allowed. However, the prescribed treatment must be first reviewed by the relevant Clinical Ethics Committee (CEC) and found to be ethically appropriate.

a. Human Biomedical Research Act 2015 2.3 The use of non-heritable gene editing for research is currently neither prohibited nor restricted by the Human Biomedical Research Act 2015. As such, non-heritable genome editing for research purposes is permitted in Singapore. b. Health Products Act 2007

2.4 Therapeutic products and active ingredients used in the manufacture of cell, tissue and gene therapy products (CTGTP) are regulated according to the Health Products Act 2007 and its subsidiary legislation, specifically the Health Products (Cell, Tissue and Gene Therapy Products) Regulations 2021. Materials used in gene therapy such as viral or non-viral vectors with genetic material, as well as clinical research materials used in non-heritable gene editing, are classified as Class 2 CTGTP. Class 2 CTGTP comprises gene modified cells, cells grown on scaffold, culture expanded cells, vectors with therapeutic gene and xeno-based products. The conduct of clinical trials and use of clinical research materials classified as Class 2 CTGTP are also regulated by the Health Products (Clinical Trials) Regulations 2016. c. Healthcare Services Act 2020 (HCSA 2020)

5 The Licence Conditions for all Acute Hospital Service, Outpatient Dental Service and Outpatient Medical Service Licensees Administering or Intending to Administer Cell, Tissue and Gene Therapy Products Manufactured In-House by Healthcare Institutions imposed under the Healthcare Services Act 2020 states that the use of in-house manufactured CTGTPs (including human cells or tissues, animal cells or tissues and genetically modified DNA/RNA carrying a therapeutic gene) for innovative salvage therapy must be reviewed by (i) the healthcare institutions’ tumour board or specialty board for that particular disease/condition, or at least two medical practitioners qualified to confirm the patient’s need for the innovative salvage therapy due to the ineffectiveness or unsuitability of current conventional therapy, and who are independent of the patient’s treatment team;

and (ii) a CEC. However, mainstream clinical applications of non-heritable gene editing are not approved for use in Singapore, nor are there ongoing clinical trials involving non-heritable gene editing in Singapore either. ii. Heritable Gene Editing for Clinical Research and Applications, and Gene Editing in Embryos or Germline Cells for Research

2.6 Heritable gene editing for clinical research and applications has not as yet secured the approval of the Ministry of Health (MOH) in Singapore, owing to the fact that there remains insufficient evidence demonstrating the safety of this novel form of technology. Research applications of gene editing in embryos or germline cells are strictly regulated in Singapore under the Human Biomedical Research Act 2015, which falls under the purview of MOH. Specific research projects involving embryonic development, which require the approval of government authorities, must adhere to the requirements set out in the Human Biomedical Research Act 2015. The BAC’s ‘Ethics Guidelines for Human Biomedical Research (2021 revised edition)’ emphasises that written approvals from government authorities such as MOH are required if the research involves human eggs and embryos.

LEGISLATIVE AND REGULATORY FRAMEWORKS FOR HNGE a. Human Cloning and Other Prohibited Practices Act 2004 7 In Singapore, the Human Cloning and Other Prohibited Practices Act 2004 stipulates that the placing of a prohibited embryo in the body of a woman is prohibited. A prohibited embryo includes any human embryo that has been developing outside the body of a woman for a period of more than 14 days, excluding any period when the development is suspended, or any embryo that is deliberately removed from the body of a woman with the intention of obtaining a viable human embryo.

The Act also strictly regulates the creation and development of human embryos for research purposes in Singapore, stipulating that a person must not develop any human embryo that is created by a process other than the fertilisation of a human egg by human sperm outside the body of a woman for a period of more than 14 days. The duration of embryonic development excludes any period for which the development of the embryo is suspended. b. Healthcare Services (Assisted Reproduction Service) Regulations 2023

2.8 Separately, the Healthcare Services (Assisted Reproduction Service) Regulations 2023 under the HCSA 2020 sets out that an assisted reproduction procedure involves (i) the collection of oocytes from a woman other than by way of surgical excision of the woman’s ovarian tissue; (ii) the fertilisation of an oocyte for the subsequent distribution of the embryo; (iii) the transfer of any oocyte or embryo into the body of a woman; and (iv) any removal of cells from an embryo for the purpose of testing the embryo. The HCSA 2020 defines an embryo as any live embryo that has a human genome or an altered human genome, and that has been developing for less than 14 days since (i) its fertilisation; (ii) the appearance of two pro-nuclei; or (iii) the initiation of its development by other means.

When point (iii) of the assisted reproduction procedure mentioned above is read together with the definition of an embryo under HCSA 2020, one can reasonably conclude that the Healthcare Services (Assisted Reproduction Service) Regulations 2023 do not prohibit heritable gene editing for infertility in Singapore. c. Human Biomedical Research (Restricted Research) Regulations 2017

2.9 The Human Biomedical Research (Restricted Research) Regulations 2017 require that every research institution and researcher in Singapore who is conducting restricted research must ensure that their research does not involve a human embryo that is more than 14 days old from the time of creation, excluding any period when the development of the embryo is suspended. The regulations also require that the research institution and the researcher ensure that only surplus embryos created in assisted reproduction treatment and embryos that are no longer required for therapeutic purposes may be used for research. While the regulations do not expressly prohibit research on heritable gene editing, specific research projects involving embryonic development would require approval from the relevant government authorities in addition to approval from the relevant IRBs.

i. Non-Heritable Gene Editing (for research and clinical applications) 2.10 Countries such as Australia, Germany, South Korea, New Zealand, the US, and the UK do not currently regulate non-heritable gene editing for research. As such, non-heritable gene editing for research is allowed in these countries. However, non-heritable gene editing for clinical applications is regulated by the US and Europe.

11 In the US, human gene editing falls under the purview of the FDA and the National Institute of Health (NIH). Gene therapy products that seek to modify or manipulate genetic expression to alter biological properties of living cells for treatment purposes are regulated by the Center for Biologics Evaluation and Research (CBER). Most products used in clinical applications of non-heritable gene editing, such as viral or non-viral vectors, are regarded as biologic drugs and are regulated with gene therapy products.

While clinical applications of non-heritable gene editing are not prohibited, they must be reviewed by the FDA pursuant to its authority under the Federal Food, Drug, and Cosmetic Act (Public Law 75-717) and the Public Health Service Act (Public Law 78-410). Meanwhile, the US NIH Somatic Cell Genome Editing (SCGE) Consortium was set up with the aim of accelerating the development of safer and more effective methods of non-heritable gene editing in patients. This is because gene editing technologies have been recognised for their potential to develop therapies for common and rare diseases caused by genetic disorders.

Therefore, improving the safety and efficacy of techniques employed in non-heritable gene editing would provide greater therapeutic options for patients.

2.12 In Europe, non-heritable gene editing, along with gene therapy and tissue engineered products, are classified as advanced therapy medicinal products (ATMPs) and are regulated by the European Medicines Agency (EMA). Specifically, the European Union’s Regulation (EC) No 1394/2007 provides an overall framework for ATMP LEGISLATIVE AND REGULATORY FRAMEWORKS FOR HNGE regulation. This also includes materials used in clinical trials for non-heritable gene editing, which is regulated by the Directive 2001/83/EC. ATMPs require licensing of clinical trials by the Medicines and Healthcare Products Regulatory Agency, and market authorisation from the EMA. The regulatory framework for AMTPs is designed to facilitate distribution of these medicines within the European Union, while also maintaining the highest level of protection for the health and interest of patients.

ii. Heritable Gene Editing for Clinical Research and Applications, and Gene Editing in Embryos or Germline Cells for Research 2.13 Countries such as Australia, Germany, Israel, South Korea, New Zealand and the US prohibit heritable gene editing for clinical research and applications. Gene editing in embryos or germline cells for research is allowed in Australia, South Korea and New Zealand while the US, however, prohibits federal funding for research carried out involving gene editing in germline cells.

2.14 In Australia, the use of human embryos in research is regulated under the Prohibition of Human Cloning for Reproduction Acts , which aims to address ethical concerns about scientific developments pertaining to human reproduction and the utilisation of human embryos by prohibiting certain practices. Practices that are completely prohibited under the Act include heritable alterations to genomes. An individual, therefore, would be committing an offence if they were to alter the gene of a human cell in such a way that the alteration is heritable, or intended to be inherited, by descendants of the human whose cell was altered. The Act also prohibits intentionally developing a human embryo outside the body of a woman for a period of more than 14 days, excluding any period when development is halted.

15 In China, any individual who is unqualified to practise medicine yet does so in contravention of law, shall be fined, sentenced to a fixed-term imprisonment of up to three years or both, criminal detention or public surveillance, depending on the severity. This is enshrined within Article 336 of the Criminal Law of the People’s Republic of China 1979 and also applies to human genome editing for clinical applications or on germline cells. He Jiankui was charged and convicted under this Article for carrying out gene editing on human embryos which were implanted into a woman and later resulted in the birth of twin girls.

The Chinese Civil Code, issued in May 2020, states that medical and scientific research activities involving human genes and embryos, among others, shall be performed in accordance with laws, administrative regulations and relevant provisions outlined by the state without endangering human health, violating moral principles or damaging the public interest. According to this framework, anyone who engages in scientific research or medical activities that contravene ethics and morality in China will be considered to have violated personal rights and can be subject to civil liabilities.

2.16 In Germany, the editing of germline cells is regulated under the Embryo Protection Act. Section 5 of the Act, which pertains to artificial alteration of human germline cells, states that anyone who artificially alters the genetic information of a human germline cell will be punished with imprisonment of up to five years or a fine. However, this does not apply to artificial alteration of the genetic information of a germ cell situated outside the body where that altered germ cell is not used for fertilisation. The Act also states that anyone who uses a human germ cell with artificially modified genetic information for fertilisation will be similarly punished.

2.17 In Israel, the use of reproductive cells that have undergone permanent intentional genetic modification (germline gene therapy) thus leading to the creation of human life, is prohibited under the Prohibition of Genetic Intervention (Human Cloning and Genetic Manipulation of Reproductive Cells) Law.

2.18 In South Korea, the Bioethics and Safety Act permits gene therapy research solely for a hereditary disease, Acquired Immune Deficiency Syndrome (AIDS) or any other disease that threatens lives or causes a severe disability, as well as for situations where there is no applicable therapy at present or where the benefit of gene therapy is expected to be significantly greater than from other therapies. Such research, South Korea’s legislation stipulates, should only be conducted before the primitive streak of the embryo appears during embryonic development. LEGISLATIVE AND REGULATORY FRAMEWORKS FOR HNGE

2.19 In New Zealand, the Human Assisted Reproductive Technology Act prohibits the implantation of a genetically modified gamete, human embryo or hybrid embryo into a human. The Act also prohibits research on non-viable embryos beyond 14 days.

2.20 The US’s National Institutes of Health (NIH) Regulation states that NIH funds may not be used for the creation of a human embryo or embryos for research purposes, or for research in which a human embryo or embryos are destroyed, discarded or knowingly subjected to risk of injury or death greater than that allowed for research on foetuses in utero under 45 CFR 46.204(b) and Subsection 498(b) of the Public Health Service (PHS) Act (42 U.S.C. 289g(b)). NIH will not fund any use of gene-editing technology in human embryos for clinical applications. III. Comparison Between Local and Overseas Legislation for HNGE a. Non-Heritable Gene Editing (for Research and Clinical Applications)

2.21 As in Singapore, the likes of Australia, Germany, South Korea, New Zealand, the US, and the UK have no legislation currently in place explicitly prohibiting the use of nonheritable gene editing in research. 2.22 The US and Europe generally regulate products of non-heritable gene editing as gene therapies to be conducted under clinical trials, similar to the practice in Singapore. However, in Singapore, in-house CTGTPs may be used for medical treatment if approved by CECs. b. Clinical research and Applications of Heritable Gene Editing and Gene Editing in Embryos or Germline Cells for Research

2.23 There is legislation in place in Australia, Germany, Israel, South Korea, New Zealand and the US, to prohibit heritable gene editing for clinical research and applications, which are comparable to the Human Cloning and Other Prohibited Practices Act 2004 in Singapore. At the same time, Australia, New Zealand, Germany and South Korea also allow gene editing in embryos or germline cells for research purposes, as does Singapore’s Human Biomedical Research Act 2015. Singapore allows research on embryos from inception to 14 days, or up until the appearance of the primitive streak, whichever is earlier. In contrast, legislation in Australia and New Zealand reference only the ‘14-day rule’, whereas South Korean legislation mentions only the appearance of the primitive streak. However, German legislation references neither the ‘14-day rule’ nor the appearance of the primitive streak.

2.24 South Korea’s laws specify that gene therapy research should only be conducted for hereditary diseases or diseases that threaten lives or cause a severe disability, and for diseases that have no applicable therapy at present. In contrast, Singapore’s Human Biomedical Research (Restricted Research) Regulations 2017 do not specify the scope of gene editing in embryos or germline cells for research purposes, as is the case for the corresponding Australian and New Zealand legislation. Separately, gene editing in embryos or germline cells for research purposes is prohibited with the use of federal funding in the US, but is not otherwise prohibited. However, unlike Singapore, the legislation in the US does not specify the need to conduct such research on embryos before 14 days, or up until the appearance of the primitive streak.

2.25 While there are no specific guidelines on HNGE in Singapore, the BAC had previously recommended in its report on ‘Genetic Testing and Genetic Research (2005)’ that the clinical practice of germline genetic modification should not be allowed. The BAC has also recommended in its report on ‘Ethics Guidelines for Human Biomedical Research (2021 Revised)’ that research involving human germline modification for purposes other than the prevention or treatment of serious genetic conditions should not be allowed, reiterating that the clinical practice of germline modification should be prohibited until there is adequate evidence from research that such clinical procedures are safe and effective.

2.26 The World Health Organization (WHO) developed recommendations on the governance and oversight of human gene editing in nine discrete areas, including human genome editing registries and illegal, unregistered, unethical or unsafe research. The International Commission on the Clinical Use of Human Germline Genome Editing recommends that a country should only allow heritable gene editing for clinical applications if it meets the criteria outlined in paragraph 2.32.

2.27 The International Society for Stem Cell Research (ISSCR) recommends against the use of heritable gene editing for therapeutic purposes but supports the use of gene editing in embryos or germline cells for research purposes. Ethics bodies such as the German Ethics Council and the Spanish Bioethics Committee on Genome Editing in Humans have also recommended against the use of heritable gene editing for clinical applications. Japan too, has published guidelines that recommend against the use of heritable gene editing for clinical applications. LEGISLATIVE AND REGULATORY FRAMEWORKS FOR HNGE V. HNGE Guidelines Which Explicitly Recommend Against Heritable Gene Editing a. The WHO Expert Advisory Committee on Developing Global Standards for Governance and Oversight of Human Genome Editing

28 In 2021, the WHO Expert Advisory Committee on Developing Global Standards for Governance and Oversight of Human Genome Editing developed new recommendations and published two reports, namely a framework for governance and its recommendations, aimed at establishing human (both heritable and non-heritable) gene editing as a means of improving public health across the world. Its framework for governance report serves to provide guidance to different groups of stakeholders to strengthen governance of gene editing technologies at the institutional, national, regional and indeed global levels.

The committee’s recommendations report pertains to both the clinical and research applications of gene editing and includes advocacy for changes to policy and practice to support the reporting of possible illegal, unregistered, unethical or unsafe non-heritable gene editing, heritable gene editing and gene editing in embryos or germline cells for research purposes. The WHO encourages all its member nations to utilise the tools for governance set out in its report on framework for governance. The WHO also advocates member nations to collaborate with it to ensure that the recommendations of the committee are implemented expeditiously.

b. The International Society for Stem Cell Research (ISSCR) 2.29 The International Society for Stem Cell Research (ISSCR) Guidelines (2021) support the use of gene editing on germline cells for research purposes only after review and approval via a specialised scientific and ethics review process. The ISSCR Guidelines also recommend that a specialised scientific and ethical oversight process may be used to assess whether the scientific objectives require the embryo to be developed in culture for a period greater than 14 days. The guidelines also recommend that research involving human embryos, in which the nuclear genome has undergone modification, are not allowed to be transferred into, or gestated in, a human uterus, as these approaches are currently deemed unsafe and raise unresolved ethical issues.

c. German Ethics Council: Intervening in the Human Germline (Opinion - Executive Summary and Recommendations) (2019) 2.30 The German Ethics Council published a report titled ‘Intervening in the Human Germline’, which called for an international moratorium on heritable gene editing for medical purposes in humans. The Council’s report serves to encourage a discussion and an evaluation of the possible goals of germline interventions in humans; determine the cases and conditions for which germline interventions may be allowable in the future; prevent premature applications of the same; and to allow time for careful basic and preclinical research to determine the safety and efficacy of heritable gene editing for clinical applications. d. Japan’s Guidelines for Research Using Gene-altering Technologies on Human Fertilised Embryos (2019)

2.31 In Japan, the Guidelines for Research Using Gene-altering Technologies on Human Fertilised Embryos support the gene editing of human embryos for research that is aimed at understanding the development of diseases, and to treat genetic diseases. These guidelines, however, recommend against germline gene editing for reproductive purposes and clinical testing. VI. HNGE Guidelines that Recommend Heritable Gene Editing be Allowed Conditionally a. The International Commission on the Clinical Use of Human Germline Genome Editing (2020)

2.32 The International Commission on the Clinical Use of Human Germline Genome Editing aims to provide a framework for scientists, clinicians and regulatory authorities to consider when assessing potential clinical applications of heritable gene editing, should heritable gene editing applications become socially acceptable in the future. It recommends that the use of heritable gene editing for treatment of diseases and infertility should be permitted only under the following conditions: a. Serious monogenic diseases that cause severe morbidity or premature death; b. Changing a pathogenic genetic variant known to be responsible for the serious monogenic disease to a sequence that is common in the relevant population and that is known not to cause disease;

c. Ensuring that no embryos without the disease-causing genotype will be subjected to the process of genome editing and transfer, and no individuals resulting from edited embryos are exposed to risks of HNGE without any potential benefit; and d. Situations in which prospective parents have no option for having a genetically related child that does not have the serious monogenic disease because none of their embryos would be genetically unaffected in the absence of genome editing; or have extremely poor options because the expected proportion of unaffected embryos would be unusually low, which the Commission defines as 25 percent or less, and have attempted at least one cycle of preimplantation genetic testing without success.

b. The World Medical Association’s Statement on Human Genome Editing 2.33 The World Medical Association issued a statement on human gene editing in 2020, in which it recommended that human gene editing should be implemented according to appropriate evidence that is collated via well-conducted and ethicallyapproved research studies. The statement added that gene editing on germline cells for research purposes should be allowed only within a separate ethical and legal framework, distinct from any ethical and legal frameworks that apply to non-heritable LEGISLATIVE AND REGULATORY FRAMEWORKS FOR HNGE

gene editing. The World Medical Association further recommends that governments should support the continued development of an international consensus, grounded in science and ethics, to determine allowable therapeutic applications of germline gene editing.

2.34 Legislation and guidelines play an important role in navigating the ethical, legal and social implications surrounding gene editing. It is imperative that researchers and research institutions adhere to these acts of legislation and guidelines in order to ensure ethical and safe utilisation of gene editing technology. These frameworks provide the necessary safeguards against potential risks from applications of gene editing technology and protect human health and societal values. This also ensures benefits of gene editing are realised in a manner that respects the autonomy and rights of all individuals and communities.

3.1 In its deliberations over the use of HNGE in biomedical research and clinical applications, the BAC remains guided by substantive and governance principles with the former including considerations of ‘Respect for persons’, ‘Solidarity’, ‘Justice’, ‘Proportionality’ and ‘Sustainability’, all of which are discussed in greater detail below: a. Respect for persons

3.2 Respect for persons behoves us to treat individuals as beings with value in themselves along with autonomy for their own life and, accordingly, to respect their right to make their own decisions without being coerced, misled or kept in ignorance. The welfare and interests of individuals are paramount, especially when their autonomy is impaired or lacking. It is this principle that underlies the importance of obtaining informed consent from potential research participants or those who are making decisions on their behalf. This applies also to entities involved in research, the protection of their privacy alongside information disclosed in confidence, and preventing or minimising harm to them.

3 In the context of HNGE, the principle of respect for persons denotes the autonomy of individuals making decisions related to biomedical research that involve gene editing or its clinical applications. The autonomy of a person may be compromised if they are not fully informed of the possible benefits, risks and repercussions that follow on from research and clinical applications of gene editing technology. , children). Individuals have the autonomy and the right to decide whether to undergo non-heritable gene editing, and the autonomous right to engage in germline human gene editing for their offspring.

Gene editing in embryos or germline cells for research, heritable gene editing for treatment of diseases, conferring resistance, enhancement of traits, and for infertility if permitted in the future, may indirectly compromise the rights, autonomy and physical integrity of the child born as a consequence of the intervention.

While gene editing does not violate the autonomy and rights of modified embryos or germline cells, since they have no autonomy per se that can be violated in the first place, some argue that it infringes the autonomy and rights of the child who is consequently born to an open future, where gene editing limits the range of set lifeoptions, since they are unable to provide consent prior to being genetically modified.

GENERAL ETHICAL PRINCIPLES IN HNGE b. Solidarity 4 The BAC takes the position that some measure of mutual obligation exists between the individual and society such that in certain specific circumstances, individual interests ought to be subordinated to achieve or promote the public good. The principle of solidarity reflects the moral obligations of individuals, such as research participants, researchers and research institutions, to share the costs associated with the design and conduct of research, including potential risks, in return for the common good.

In the context of biomedical research, acceptance of agreed social benefits is typically considered a public good, thus supporting an in-principle willingness to consider participation in research that yields the accepted benefits. There is also a need to balance the interests of the public or society with the rights and interests of individual participants such that individual interests are not unnecessarily sacrificed but are also advanced for the public good. This would help resolve incompatible and irreconcilable perspectives on the good or right thing to do.

3.5 Solidarity reflects the importance of general altruism and other pro-social motives as a basis for participation in biomedical research. For instance, research in human gene editing may reap benefits for society by enabling faster and more accurate diagnosis of diseases or patient conditions, introducing more targeted treatments and enabling early prevention of genetic disorders. While biomedical research is important in realising the long-term benefits from the applications of gene editing, it is also crucial to note that misuse and abuse of such technology for inappropriate purposes, or to effect personal trait preferences, could lead to the neglect or failure to discharge obligations towards certain subgroups, such as those suffering from rare diseases. c. Justice

3.6 The principle of justice encompasses the general principles of fairness and equality for all individuals, which implies that access to the benefits of biomedical research and the burden of supporting it, should be shared across society equitably. This principle also includes rights-based justice, which focuses on ensuring that individuals’ rights are respected and protected throughout the research process. In the event of research yielding an immediate benefit that could be applied to research participants, the principle of justice would dictate that the benefits are shared with them fairly, as a way of reciprocating their contribution to the research. The principle of justice also implies that researchers and their institutions shoulder some responsibility for the welfare of participants in the event of adverse outcomes arising directly from their participation in the research.

7 In the context of research and clinical applications of HNGE, justice requires that gene editing technology and therapy are accessible to the public according to a plausible theory of justice. However, the technology involved may raise concerns about ensuring fair access to therapy due to the high cost incurred. As such, treatments involving the use of gene editing technology may not be widely or readily accessible to the entire population, particularly among lower socioeconomic status groups, an inconsistency that may lead to disquiet about societal inequity.

Gene editing technology could also inadvertently reinforce negative bias or create new forms of discrimination, further prejudicing marginalised groups. Ensuring justice in this context involves not only equitable access to HNGE technology, but also addressing potential stigmas and promoting inclusive attitudes towards individuals with disabilities. d. Proportionality

3.8 The principle of proportionality requires that the regulation of research should be proportional to the degree of possible threats to autonomy, individual welfare or the public good. As such, interference with individuals’ decisions and/or actions should not exceed what is needed to achieve necessary regulation to promote the public interest. This principle also implies that the risk in any acceptable programme of research, and the stringency of its regulation, should not be disproportionate to any anticipated benefits.

3.9 When assessing the use of gene editing technology in biomedical research or clinical purposes, the potential benefits to individuals and society brought about by the editing of the human genome should outweigh the anticipated risks of such research and clinical applications. The stringency of any regulation or governance framework developed for research employing gene editing, including a de facto prohibition of specific research activities, must be proportionate to the risks being mitigated.

3.10 Heritable gene editing interventions may be more acceptable for serious or lifethreatening diseases or conditions when no alternative interventions or treatments are available, as the benefits of such applications may outweigh the risks in these circumstances. However, they might be less acceptable when used for conferring resistance against diseases, enhancement of traits or to treat infertility. Hence, researchers and clinicians should determine the aim of the gene editing intervention or research and balance potential benefits against associated risks. e. Sustainability

3.11 The principle of sustainability is understood broadly, to support arguments for the conservation of nature and the minimisation of resource depletion for the good of the planet. Therefore, research processes and outcomes should not unfairly jeopardise or prejudice the welfare of future generations.

3.12 In the context of human gene editing in biomedical research or for clinical purposes, it is recognised that gene editing technology can bring about social benefits. This includes research involving human embryos and heritable gene editing for the treatment of diseases, conferring resistance, enhancement of traits, or treatment for infertility. However, such research might harm the offspring and future generations, directly or indirectly, due to the risks of genetic mutation. Researchers and research institutions are encouraged to allocate and expend research resources to support HNGE research activities, as long as they align with the United Nations (UN) Sustainable Development Goals and are not misused. GENERAL ETHICAL PRINCIPLES IN HNGE

3.13 In addition to the five substantive principles discussed above, the BAC has also identified three governance principles as key in the context of HNGE in biomedical research and clinical applications. These three principles aim to guide researchers and institutions in ensuring that an appropriate approach to govern gene editing for research purposes and clinical interventions is adopted. a. Inclusivity

3.14 Biomedical research and clinical care that is conducted in Singapore should reflect the diversity of the country’s population and their benefits should be made accessible worldwide. The advancement of health equity through research is promoted by community engagement and participation. Stakeholders may be engaged by means of dialogue, public consultation and consensus-building within the local community.

3.15 In the context of HNGE, the benefits of research and potential clinical applications of the technology are considered a public good and should be accessible to everyone. However, the ethical implications of HNGE could further widen already divergent views about technology in society, especially among groups aligned by different social, cultural and religious tenets. Hence, there is a need to carefully consider the knowledge and perspectives about HNGE as informed by different social, cultural and religious beliefs. It is important to also work closely with the various groups of people to facilitate ‘community-engaged research’, where a wide array of opinions and perspectives are considered during the conceptualisation of research plans.

3.16 Decision-makers should consider the views of all stakeholders, taking them into account wherever possible. Appropriate stakeholders such as patients, prospective parents and the wider public as a whole should be consulted and engaged, to identify, prioritise and reach consensus on the specific areas, topics or questions that the research employing gene editing aims to address. This engagement can help researchers understand the needs and concerns of its stakeholders. Meaningful stakeholder engagement occurs when there is an opportunity to influence future

While the principles of beneficence and non-maleficence are not listed explicitly among the BAC’s five substantive principles mentioned above, these two principles are instantiated by some of the five principles. • Solidarity and beneficence: Beneficence preserves individual human welfare, which should be taken into consideration when social benefits are weighed (i.e., principle of solidarity). Proportionality and beneficence: The benefits to individuals (i.e., beneficence) need to be considered when risks and benefits are weighed (i.e., proportionality).

• Sustainability and non-maleficence: Both principles focus on minimising possible harm, butsustainabilityapplies this to the future generations, whereas non-maleficence focuses on individual welfare. outcomes. In the context of human gene editing in biomedical research, this may include input into research design, ethical oversight or overall governance of the research and its findings. b. Transparency

17 Transparency corresponds closely to ethical responsibility and moral and legal liability for the decisions and actions arising directly from research studies that should be attributed to researchers and their institutions. Research methods, analysis and data must be reported and disseminated openly, clearly, comprehensively and in a timely manner. Transparency in the reporting of research not only helps ensure that results are reproducible and reliable, but this principle also facilitates proper interpretation and dissemination of findings by other researchers.

Transparent reporting mechanisms may also be set up to investigate concerns and possible unlawful actions, as well as to provide support and protection for whistle-blowers. To allow meaningful input from stakeholders such as the public into policy development with regard to the use of HNGE, it is incumbent upon policymakers to institute policies, frameworks and recommendations for research and clinical applications of technologies, including novel and upcoming ones, in a transparent way, so as to promote and uphold public confidence.

Meaningful public input with regard to allowing or forbidding HNGE technologies may need to be incorporated into the policy-making process, where government decisions should be subject to transparent social debate. c. Responsible Stewardship of Science

3.18 The principle of responsible stewardship of science refers to the moral requirement to be prudent about resources and to have responsible oversight of all elements, including planning, management and decision-making in research activities in the pursuit of any emerging field in biomedical research. Both evidence-informed basic and applied research need to be pursued with appropriate caution given the uncertainty and risks involved. Established ethical practices, ethical guidelines and legislation should be observed when conducting research on humans, with particular attention given to issues of integrity and conflicts of interest. Research priorities should also be determined by considering the needs of society and how to achieve the maximum social and scientific benefits of research while minimising the potential risks.

3.19 In the context of HNGE in biomedical research, responsible stewardship of science requires that the processes and outcomes of HNGE research are aligned with the values, needs and expectations of society, as identified by stakeholder engagement. This extends beyond the dissemination of information and requires taking into consideration the views of all stakeholders, as elaborated earlier under the principle of inclusivity.

3.20 In addition, there should be oversight mechanisms in place to ensure research activities are conducted appropriately. For instance, an advisory group could be established within research institutions to oversee the research priority-setting process for gene GENERAL ETHICAL PRINCIPLES IN HNGE

editing research. The group may comprise members from diverse backgrounds (e.g., research, medical, administrative) to advise on the current policy and research considerations, assist with the identification of stakeholders and provide inputs in finalising the research priorities. It is important for researchers and institutions to exercise appropriate caution, given the uncertainty and long-term risks of using gene editing technology in both research and clinical applications. There is also a need to ensure that there are clear and well-established protocols and processes for oversight and review, to ensure that research is conducted in an ethical manner.

4.1 Techniques and tools developed for HNGE have evolved ever since the inception of the technology. Nonetheless, the general steps involved in gene editing for research are similar across these techniques, beginning broadly, with targeting the area of deletion and the subsequent insertion of genes within the genome by introducing proteins or enzymes to cleave the DNA strands. The target DNA is then removed before insertion of replacement DNA or modification/disruption of the gene. The replacement DNA is typically used as a template for repairing the break and generating a healthy form of the gene (see Fig. 4.1). Figure 4.1: Flowchart Showing the General Steps Involved in Gene Editing Step 1: Area of deletion and subsequent insertion is targeted and proteins/ enzymes are introduced to cut the DNA strands Step 4: The replacement DNA is used as the template to repair the break Step 2:

Removal of target DNA Step 3A: Insertion of replacement DNA Step 3B:

4.2 Besides directed genetic alterations, epigenetic modifications can also be made to DNA to regulate its expression by turning the genes on and off and influencing protein production in cells. Unlike gene editing, such processes are reversible, as they do not change the DNA sequences on the genome (Fig. 4.2). As the focus of this report is on heritable genetic changes resulting from human gene editing that causes changes in the DNA sequence, epigenetic modification and its technologies will not be discussed in detail, given that epigenetic modification involves alterations of DNA accessibility and chromatin structure instead of DNA sequence to regulate patterns of gene expression. Figure 4.2: Cell Diagram Illustrating Gene Editing, Epigenetic Modification, and Cell and

4.3 While there are many types of gene editing technologies, such as restricted enzymes, Insertion Sequence (IS) elements, retrons, and meganucleases, the core technologies that are now most commonly used by scientists and researchers to facilitate gene editing are ZFNs, CRISPR-Cas9 and TALENs (Fig. 4.3 and 4.4). Gene therapy: Introducing genetic material into cell Cell therapy: Cells engineered as the therapeutic product Nucleus Cell Genomic DNA Gene editing: Changing the DNA sequences (A, T, C, G) on the genome. Epigenetic modification: Changing the chemical modifications on the genome without changing the sequence *not the focus of this report Figure 4.3: A Simplified Overview of the Different Types of Gene Editing Technologies CRISPR-Cas9 Definition:

CRISPR-Cas9 is a DNA or gene editing tool that cuts DNA at precise locations, allowing for its accurate and targeted renewal or replacement. New gene editing techniques using the CRISPR-Cas9 system: • Base editing: Making precise changes in DNA without causing doublestrand breaks. • Prime editing: Making targeted small insertions, deletions, and base swapping in a precise way, without the need for donor DNA templates. It uses a donor Ribonucleic Acid (RNA) template and a reverse transcription mechanism. TALENs Definition: TALENs are artificial restriction enzymes and can cut DNA strands at any desired sequence.

Example of research studies that used TALENs: • Researchers in the UK demonstrated the firstin-human use of TALEN gene-edited T-cells in two infants with refractory relapsed B-cell acute lymphoblastic leukaemia. This therapeutic application of TALEN-engineered cells highlights the feasibility and potency of gene-editing strategies for the delivery of antitumour immunity. ZFN Definition: ZFNs are synthetic proteins used for gene targeting to introduce insertions or deletions at cut sites in the genomes of living cells. Example of research studies that used ZFN: • Gene editing clinical trial in the US used ZFN product GRm13Z40-2 for the treatment of stage III or IV malignant glioma patients in 2010.

HNGE TECHNIQUES/TECHNOLOGIES AND THEIR RELATIONSHIP WITH GENE AND CELL THERAPIES CRISPR-Cas9 Definition: • CRISPR-Cas9 consists of a homing device (the CRISPR part) that guides molecular scissors (the Cas9 enzyme) to a targeted section of DNA. • The CRISPR-Cas9 system acts in a sequence-specific manner by recognising and cleaving foreign DNA. CRISPR-Cas13 is a related system that cleaves RNA. New gene editing techniques using the CRISPR-Cas9 system:

• Base editing: Cytidine base editors and adenine base editors, for example, allow the introduction of point mutations in the DNA without generating double stranded DNA breaks (as seen in the conventional CRISPR- Cas9 system). There are two classes of base editors. Cytosine base editors convert cytosine to thymine. Adenine base editors convert adenine to guanine. Base editing does not require donor DNA templates.

• Prime editing: Prime editing uses the cell’s intrinsic DNA mismatch repair mechanism, enabling targeted editing without generating double-stranded DNA breaks and allows for targeted insertions to be achieved without the need for donor TALENs Definition: • TALENs are DNA-binding domains that can be engineered to cut specific sequences of DNA. • TALENs are made by fusing a transcription activator-like (TAL) effector DNA-binding domain to a DNA cleavage domain. Example of research studies that used TALENs:

• Researchers in the UK demonstrated the first-inhuman use of TALEN geneedited T-cells in two infants with refractory relapsed B-cell acute lymphoblastic leukaemia, and this therapeutic application of TALEN-engineered cells highlights the feasibility and potency of gene-editing strategies for the delivery of antitumour immunity. ZFN Definition: • ZFNs are a class of synthetic DNA-binding proteins that are used for targeted genome editing by generating double stranded breaks (DSBs) on targeted DNA to create an insertion or deletion (indel) for disrupting the gene function.

• ZFNs use DNA binding domains (also known as zinc fingers) that recognise ~ 3 bp sequences linked together to generate arrays which allow desired DNA sequences to be targeted. Example of research studies that used ZFN: • A study conducted in the US used a human lymphoblast cell line derived from chronic myeloid leukaemia (CML) patients, and a custom designed ZFN to deliver site-specific double strand breaks to the telomeric portion of the mixed lineage leukaemia (MLL) gene breakpoint cluster region as well as to analyse chromosomal rearrangements associated with MLL leukaemogenesis via DSB error repair. • Gene editing clinical trial in the US used ZFN product GRm13Z40-2 for the treatment of stage III or stage IV malignant glioma patients in 2010.

IV. The Relationship between Gene Editing, Gene Therapy, and Cell Therapy

4.4 Gene editingresults in permanent alteration of the genetic material of a living organism by inserting, replacing or deleting a DNA sequence at a particular location in the genome. Gene editing targets the genetic sequence of interest and introduces breaks or chemical modifications to the DNA. In gene editing, breaks among DNA strands are repaired via one of two pathways: homology-directed repair (HDR) or non-homologous end-joining (NHEJ). HDR takes place when a replacement DNA is inserted and used as a template to repair the break, while NHEJ repairs the break without the need for a replacement DNA to act as a template. NHEJ is the less accurate pathway for repairing Cas9-induced DNA double strand breaks and is also the more difficult pathway in terms of controlling outcomes. Gene editing may be carried out using gene editing tools such as ZFNs, CRISPR-Cas9 and TALENs.

4.5 Gene therapy refers to the treatment of a patient by altering their genetic composition with exogenous DNA. This may involve using an extra-chromosomal DNA that is not subsequently integrated into the subject’s genome, or the modification of the genome via gene editing. Gene therapy is a technique employed to change an individual’s genetic makeup with the intent of treating or curing genetic diseases and can work by: a. Replacing a disease-causing gene with a healthy copy of the gene; b. Inactivating a disease-causing gene that is dysfunctional; c. Introducing a new or modified gene into the body to help treat a disease; or d. Correcting disease-causing mutations.

Gene therapy may be performed either in vivo, whereby the therapeutic gene is delivered directly to cells inside the patient’s body, or ex vivo, where the therapeutic gene is inserted into cells outside the body before being introduced into the body. Ex vivo gene therapy is also a form of cell therapy. Gene therapy is generally carried out using genetically modified cell-based immunotherapies, viral vectors, gene editing, and non-viral vectors.

6 Cell therapy denotes the introduction of new cells into a patient’s body to grow, replace or repair damaged tissue in order to treat a disease. The treatment regimen may employ cells from the patient’s own body (autologous) or from a donor (allogenic). Cell therapy includes stem cell-based and non-stem cell-based unicellular or multicellular therapies, as well as a variety of different types of cells such as stem cells, lymphocytes, dendritic cells, and pancreatic islet cells.

In some cases, such as Chimeric Antigen Receptor – T (CAR-T) and Chimeric Antigen Receptor – Natural Killer Cell (CAR-NK) cell therapies, cells are genetically modified before they are (re)introduced into the patient. This technology interlinks gene therapy and cell therapy. Gene editing techniques such as CRISPR-Cas9, base editing and prime editing may also be applied to correct genetic mutations and/or introduce beneficial edits in targeted stem cells. Gene-edited stem cells are currently, and increasingly, being investigated as a new therapeutic modality. HNGE TECHNIQUES/TECHNOLOGIES AND THEIR RELATIONSHIP WITH GENE AND CELL THERAPIES

Various studies have shown that genome editing results in priming of stem cells for better therapeutic efficacy, delayed disease progression and protection against genetically driven diseases. Figure 4.5: Applications of Gene Editing, Gene Therapy, and Cell Therapy V. Similarities and Differences between Gene Therapy and Gene Editing

7 Gene therapy and gene editing, the latter being employed in gene therapy, both target the genetic cause of diseases, such as a variant or mutation in a gene, and treat or halt progression of the disease using genetic material. While gene editing and gene therapy are both used for therapeutic purposes, gene editing does so by delivering genetic material or proteins that can directly edit and change the information that the DNA encodes for in order to correct the protein produced by the DNA and restore proper cellular function.

Nonetheless, gene therapy delivers a working gene into a cell using carriers like viral vectors, such as adeno-associated virus (AAVs) and lentivirus vectors, or non-viral vectors such as liposomes to effect the therapy. Gene therapy is used solely for therapeutic purposes while gene editing has applications beyond therapeutics, such as understanding disease development, conferring resistance, reducing predisposition to diseases, enhancement of traits, as well as other nontherapeutic applications of technology underlying human gene editing. VI. Similarities and Differences between Cell Therapy and Gene Editing

4.8 Cell therapy and gene editing share the objective of modifying the underlying biological mechanism of a disease, by either introducing functional cells (i.e., cell therapy), or altering the genetic material of a living organism (i.e., gene editing). Gene editing technologies, such as CRISPR-Cas9 in particular, are currently being used in cell therapies. While cell therapy provides treatments for inherited or acquired diseases where whole cells are infused or transplanted into a patient, gene editing corrects genetic diseases using enzymes, particularly nucleases that have been engineered to target a specific DNA sequence. Gene editing introduces cuts or chemical modifications into the DNA strands, such that the existing DNA sequence may be changed to another sequence. POTENTIAL RESEARCH AND CLINICAL APPLICATIONS OF HNGE AND CURRENT ESTABLISHED METHODS TO TREAT DISEASES

I. Potential Application of HNGE in Research to Understand Diseases or Cancer Development 5.1 Gene editing technology has enabled enzymes such as nucleases to be engineered as biological tools to introduce specific modifications at specific sites within the genomic DNA. Such targeted gene modifications effected by chimeric gene editing tools (e.g., ZFNs, TALENs, and CRISPR-Cas9) are powerful methods of assessing gene function as well as to precisely manipulate cellular behaviour and function. In particular, developments in gene editing technologies have been leveraged by investigators to understand the aetiology behind various diseases and elucidate underlying molecular mechanisms that may be used for better therapeutic strategies.

5.2 Gene editing technology has been applied in research for various purposes and indications. Some examples of research conducted using gene editing technology to understand diseases and cancer development are discussed as follows: a. Cancer research

3 Cancer arises as a result of genomic changes leading to the growth of tumour cells, where undesirable mutations in the gene may lead to the production of proteins harbouring aberrant functions and resulting in uncontrolled cell growth. Gene editing tools such as CRISPR-Cas9 are being used in the field of cancer research to target specific regions of the genome within the cancer cells to understand the causative mechanisms of tumorigenesis and development.

For instance, a study conducted in Japan in 2015 modelled colorectal cancer by introducing multiple genetic mutations in human intestinal organoids using CRISPR-Cas9, which allowed researchers to understand the mutation pathway driving cellular growth in the tumour microenvironment. In a similar vein, CAR T-cells and CAR NK-cells have been engineered using CRISPR-Cas9 to specifically target tumour cells. This area of research is also receiving much attention in the pursuit of more effective treatment modalities in cancer.

b. Neurodegenerative Diseases 4 Neurodegenerative diseases (NDs), such as Alzheimer’s, Huntington’s and Parkinson’s diseases, are debilitating conditions, each having poor prognosis and clinical outcomes due to the lack of precise diagnostic tools and definite treatments. Studies have found that genetic mutations are one of the causes of neurodegeneration. For example, familial Alzheimer’s disease results from mutations in the amyloid precursor protein (APP) and presenilin (PSEN1 and PSEN2) genes, which result in increased production of the amyloid-beta protein responsible for the onset of the neurodegenerative disease.

As such, gene editing may offer a novel and promising way of developing ND models for interrogating disease mechanisms as well as to help discover potential drugs for treatment. In 2016, a research group in Rockefeller University (US) generated human-induced pluripotent stem cells (iPSCs) with mutations in the APP and PSEN1 genes using CRISPR-Cas9 to study the early onset of the disease. c. Hereditary Eye Diseases

5.5 Ocular diseases present with a variety of clinical manifestations, brought about by intrinsic genetic mutations or by external environmental factors. Gene editing technology has been used to probe the mechanisms of hereditary eye diseases too. For example, a research study carried out in China in 2018 employed genetic editing to investigate the molecular mechanism of an inherited retinopathy, retinitis pigmentosa, due to mutation in a GTPase regulator RPGR, which resulted in disorders of the cones and rods in the eye. The study discovered that the correction of the causative mutation in RPGR via CRISPR-Cas9 reverses ciliopathy and rescues photoreceptor loss by restoring gene expression, thus demonstrating the use of CRISPR-Cas9 as a mutation repair strategy. II. Potential Application of HNGE in Research to Understand the Development of Human Embryos

5.6 The use of human embryos in biomedical research has been heralded as beneficial to the study of human embryo development and understanding of birth defects. In the context of gene editing technology, research involving human embryos may be carried out to potentially discover and develop new treatments for genetic or complex diseases, to enhance the longevity of healthy individuals by delaying ageing and to produce designer babies. In particular, gene editing tools enable the uncovering of the role of specific genes in embryo development in relation to physiology, disease development, pregnancy and miscarriages. In doing so, the underlying genetic causes of these maladies may be established to facilitate the finding of new treatments. POTENTIAL RESEARCH AND CLINICAL APPLICATIONS OF HNGE AND CURRENT ESTABLISHED METHODS TO TREAT DISEASES

5.7 Human embryos may also be used to construct new disease models for unravelling pathologies of genetic diseases. Screening methods for drug discovery and development in human embryos may be developed for genetic diseases arising from exposure to toxic substances and evaluate potential therapeutic agents for cure. However, it is imperative that the use of gene editing technology for such purposes be further refined and validated before being considered as a therapeutic option.

8 Consistent with the use of human embryos for other research purposes, the 14- day rule should be applied for any nuclear gene editing research carried out in human embryos. This rule stipulates that biomedical research is allowed only in early human embryo development. It is prescribed in science policy and regulation to limit all research work carried out on human embryos up to a maximum of 14 days after their creation, or to the equivalent stage of development that is normally attributed to a 14-day-old embryo. , beyond 14 days) of allowable research in early embryo development. , legislators, medical practitioners and scientists) and indeed the wider public, to ensure that the views of scientists and laymen alike are considered before any changes to the 14-day rule are made.

5.9 In 2017, researchers from The Francis Crick Institute (UK) employed CRISPR-Cas9- mediated gene editing to investigate the function of the pluripotency transcription factor Octamer-binding transcription factor 4 (OCT4) during human embryogenesis. OCT4 was specifically targeted in human zygotes (fertilised human eggs) and found to disrupt blastocyst development. Such studies exemplify the potential of gene editing as a powerful tool for studying early human development. III. Potential Application of Technology Underlying HNGE as Diagnostics and Drug Discovery Tools

5.10 Rapid and accurate methods of diagnosing diseases are equally and increasingly important in detecting the onset of symptoms and allowing for early interventions. While nucleic-acid-based sensors are the most specific and sensitive, given that trace amounts of DNA and ribonucleic acid (RNA) can be readily amplified and recognised via complementary base-pairing, such technologies require costly equipment and skilled personnel. CRISPR-based diagnostics, such as the CRISPR-Cas9 system, circumvent these issues through a target-specific binding mechanism that is based on nucleotide sequence, and enable the technology to advance diagnostic methods in detecting the disease-related gene, microRNAs, and genetic variations such as single nucleotide polymorphism (SNP) and DNA methylation.

5.11 CRISPR-based diagnostics not only allow for a faster and more accurate diagnosis of diseases in the clinic, but also bolster progress in the field of personalised medicine, such as by enabling point-of-care testing (i.e., testing is conducted near a patient/ person outside a clinical laboratory setting) by untrained personnel at the individual’s home. CRISPR-Cas9 diagnostics may be categorised into two broad classes, six types and several subtypes based on evolutionary relationships. While applications of CRISPR as diagnostics are mostly still in development, three of note are discussed here: a. Diagnostic Tool: Specific high sensitivity enzymatic reporter UnLOCKing (SHERLOCK)

12 SHERLOCK is a CRISPR-based diagnostic system that is guided by RNA, and which was developed in 2017 by the Broad Institute. This technology is able to identify lowfrequency mutations in cancer cells that are not easily identifiable by other sequencing methods and may be used to detect specific viral strains as well as differentiate between bacterial strains. Similarly, in Nigeria where a Lassa fever epidemic claimed the lives of approximately 69 people in 2019, a new CRISPR-based diagnostic test has been developed to detect the viral infection. The test relies on CRISPR’s ability to detect RNA from the Lassa virus.

If the approach is successful, the test could be further programmed to detect a wide range of viral infections including dengue, Zika and strains of the human papillomavirus (HPV), allowing treatments to be administered early. Consequently, healthcare workers would be able to curb the spread of infections such as these. b. Diagnostic Tool: DNA endonuclease targeted CRISPR trans reporter (DETECTR)

5.13 In 2018, a CRISPR-based diagnostic method, DETECTR, which harnesses the ability of the Cas12a single-stranded DNase (ssDNase) to generate single-stranded DNA breaks, was developed in combination with isothermal amplification. The diagnostic tool is highly sensitive and has provided a simple platform for rapid and specific detection of human papilloma virus (HPV) in patient samples, displaying promise in molecular diagnostics. c. Personalised Treatment

5.14 CRISPR-Cas9-based screening for identifying new drug targets and biomarkers represents another avenue in precision medicine. This is particularly relevant in cancer studies due to the heterogeneity in tumour cells and the underlying genetic causes responsible for their resistance to drug treatment. Targeted gene editing approaches employing CRISPR can be used not only in high-throughput screening to discover novel therapeutics but also in elucidating pathways driving drug resistance in cancer cells, and ultimately, leading to the development of personalised treatments for patients. POTENTIAL RESEARCH AND CLINICAL APPLICATIONS OF HNGE AND CURRENT ESTABLISHED METHODS TO TREAT DISEASES IV. Potential Application of HNGE to Confer Resistance to Certain Diseases and for Genetic Enhancement

5.15 Gene editing has been explored for its potential application to enhance or confer disease resistance in individuals. This could be achieved by altering genes commonly found among the general population to variants that are known or expected to be beneficial, thereby enhancing certain traits of the individual. For instance, the β-globin (HBB) gene in the genetic blood disorder beta-thalassaemia was first modified in zygotes in 2015. However, findings from this study showed low efficiency in genetic recombination, as well as genetic mosaicism and off-target cleavages. It is also worth noting that while gene editing has been widely used for research in the field of disease treatment, there is scope for gene editing tools to be misused to prevent certain diseases or enhance certain features.

16 The controversy over the use of gene editing to confer resistance against disease can be illustrated by the experiment conducted by He Jiankui in China. , one partner is HIV-positive and the other is HIV-negative) to prevent their offspring from being infected and led to the birth of genetically enhanced babies. He had used CRISPR-Cas9 to modify the CCR5 gene in human embryos with the intention of producing babies with an increased resistance to HIV infections.

CCR5 is a co-receptor expressed on the surface of immune cells involved in the signalling and coordination of immune responses, acting like a ‘door’ that allows the HIV entrance into the cell and thereby playing an essential role in HIV pathogenesis. The mutation in the CCR5 gene locks “the door”, which prevents HIV from entering the cell. However, He failed to consider the possible off-target effects of the technique used, the downstream effects associated with heritable gene editing and possible health risks to the offspring.

This led to criticisms of his procedure, which was labelled as risky, ethically contentious and medically unjustified (see Chapter 7 for a detailed discussion on the ethical issues). While the same approach to introduce the mutation to the same gene in zygotes has been reported previously, mosaicism and low efficiency of the gene editing were observed in the zygotes. Hence, the fidelity and maturity of gene editing technology for the purpose of enhancing specific traits have to be clearly evaluated before the technology can be approved for widespread use.

V. Potential Application of HNGE for Polygenic Editing to Reduce Predisposition to Diseases 5.17 Gene editing strategies that are being developed or studied in clinical trials largely target lethal diseases that are typically associated with single nucleotide variants (SNVs) and are relatively less prevalent among the general population. Polygenic or complex diseases, on the other hand, are attributed to multiple genetic variants. CRISPR may be used to perform multiple edits to the gene simultaneously to address polygenic diseases caused by the combined action of more than one genetic variant or mutation.

18 Multi-gene editing has been reported in several instances. In 2022, engineers at Rice University developed the “drive and process” (DAP) array, a streamlined CRISPR-based technology that is able to correct dozens of errors simultaneously with high precision and efficiency. The approach is time-efficient and has been shown to work in human cell models for heart disease, Type 2 diabetes, muscular dystrophy, sickle cell disease and beta thalassaemia caused by a combination of mutations. Separately, Verve Therapeutics announced in July 2022 that a clinical trial would be conducted for their gene therapy, named VERVE-101.

This first-in-class gene editor converts an adenine base to a guanine base within the gene, encoding a protein called PCSK9, which is a key regulator of blood cholesterol levels. Disabling PCSK9 has been shown to be able to reduce cholesterol levels and, by extension, the risk of heart diseases. Therefore, the trial aims to study the efficacy of lowering levels of functional PCSK9 in individuals with heterozygous hypercholesterolaemia, a condition that causes high cholesterol, which may lead to cardiac complications. VI. Potential Application of HNGE to Correct Disease-causing Mutations as a Therapeutic Strategy

5.19 Gene editing for the treatment of diseases is widely studied due to its potential to correct aberrant genetic mutations with a high degree of precision and accuracy. Gene editing tools such as CRISPR are not only employed to study mutations in diseasecausing genes, but more importantly, they can be used to correct mutations for the treatment of diseases, which are discussed as follows: a. Human Immunodeficiency Virus (HIV)

20 HIV is a major public health concern, infecting millions around the world and causing widespread deaths as many succumb to its complications every year. However, there is as yet no effective vaccine or cure for HIV infections. The current prescribed treatment for HIV infections involves combination antiretroviral therapy (cART), which targets the replication cycle of the HIV virus, and is a life-long treatment. The development of anti-HIV therapy is particularly challenging, due in large part to a poor understanding of HIV reservoirs, from which the virus may persist and regenerate upon integration into the cellular genome.

Gene therapy, which is used to target and inactivate integrated viral genomes, provides an alternative pathway to achieving a functional HIV cure. For example, research conducted in the US in 2014 focused on the NHEJ-mediated POTENTIAL RESEARCH AND CLINICAL APPLICATIONS OF HNGE AND CURRENT ESTABLISHED METHODS TO TREAT DISEASES inactivation of the CCR5 gene in autologous CD4 T-cells of persons infected with HIV using ZFNs. The study found that infusion of the CCR5-modified CD4 T-cells was feasible and generally safe, although limited by the small sample size. b. Spinocerebellar Ataxia

21 Spinocerebellar ataxia refers to a class of rare neurodegenerative diseases that is autosomal, dominantly inherited and manifests in the loss of various cognitive and motor functions. Potential treatment options for the disease typically include pharmacological interventions as well as speech and physiotherapy. Most conditions associated with spinocerebellar ataxia are caused by higher than normal levels of genetic sequence coding for glutamine, due to polyglutamine-encoding repeat expansions within the gene, which results in protein aggregation and cell death. This may be corrected by gene editing.

A study conducted in China in 2021 demonstrated the feasibility of CRISPR-Cas9-mediated homologous recombination strategy to precisely repair spinocerebellar ataxia Type 3 in iPSCs and reverse the corresponding abnormal disease phenotypes such as mitochondrial dysfunction and oxidative stress disorders. c. Spinal Muscular Atrophy (SMA)

5.22 Spinal Muscular Atrophy (SMA) is a neuromuscular disease caused by mutations in the Survival Motor Neuron 1 (SMN1) gene where outcomes of existing therapies have been suboptimal. Gene editing may be employed to restore the levels of SMN protein expression by precisely editing Survival Motor Neuron 2 (SMN2), promising a new treatment option for SMA. For instance, the US Food and Drug Administration (FDA) approved the first gene therapy, onasemnogene abeparvovec (or Zolgensma™), for the treatment of SMA for children under 2 years of age. Zolgensma™ is a biologic administered intravenously to deliver the SMN1 transgene as well as synthetic promoters, using viral capsids as delivery vectors, that could promote the expression of functional SMN and improve muscle activity in a child with SMA. d. Beta-Thalassaemia

23 Beta-thalassaemia is a genetic blood disorder caused by beta-chain deficiency in haemoglobin production. The standard treatment for beta-thalassaemia is allogeneic bone marrow transplantation (BMT) from a completely matched donor, which requires long-term use of immunosuppressants and may invoke other immunological complications such as higher susceptibility to infections as well as graft-versus-host diseases. Gene editing applied to beta-thalassaemia can treat the disorder without involving the use of immunosuppressants and graft-versus-host disease prophylaxis, garnering attention to the modality for treatment of this disease.

For example, the first attempt to correct mutation in the HBB gene responsible for beta-thalassaemia in human embryos was reported in a study conducted in China in 2017. The CRISPR-adapted base editing tool was shown to precisely modify the HBB gene with efficiency of over 23% and repaired more than 20% of the blastomeres, although this study observed mosaicism in the edited embryos. In 2019, Allife Medical Science and Technology Co. Ltd. conducted a clinical trial for the application of CRISPR-Cas9 in the treatment of beta-thalassaemia.

In the study, the HBB gene was corrected in induced haematopoietic stem cells (iHSCs) derived from patients and transfused intravenously back to the subjects, demonstrating the potential of gene therapy to treat beta-thalassaemia. VII. Current Established Methods of Treatment/Prevention of Diseases in Individuals or Offspring

5.24 This section will discuss only the scientific and medical advantages and disadvantages of the current established methods of treating or preventing diseases in individuals or future offsprings. The ethical issues involved in the applications of HNGE are discussed in depth in the subsequent chapters (i.e., from Chapters 6 to 10). a. Conventional treatments

5.25 While gene editing offers new and promising strategies in the treatment of severe diseases that currently lack effective cures, the technology is still in development and requires considerable scrutiny prior to approval for widespread clinical application. Hence, conventional treatments (e.g., chemotherapy, radiation or surgery for cancer) remain the primary choice of therapy or clinical management, even though the safety and efficacy of non-heritable gene editing is more well-established than that of heritable gene editing.

5.26 Conventional treatments are generally regarded to be safe for clinical use and have demonstrated good clinical efficacy, as they have been put through rigorous scientific testing and clinical trials. Therefore, prescribing treatment regimens with conventional therapies and established management or procedures would be desirable for patients. However, conventional treatments may not be effective for patients who have developed resistance to treatments (e.g., chemotherapy resistance in cancer), suggesting that other forms of therapeutics such as gene editing may be required. b. Prenatal testing or No testing

5.27 Prenatal testing refers to tests carried out during pregnancy to assess a pregnant woman and the health of her foetus, consisting primarily of prenatal screening and prenatal diagnosis. Screening tests are used to identify the likelihood of abnormalities POTENTIAL RESEARCH AND CLINICAL APPLICATIONS OF HNGE AND CURRENT ESTABLISHED METHODS TO TREAT DISEASES

of the foetus (e.g., birth defects and genetic disorders) while diagnostic tests are invasive tests that confirm the preliminary outcomes obtained from the screening test. Prenatal tests comprise maternal blood or saliva tests, urine tests, ultrasound (including nuchal translucency), amniocentesis, Chorionic Villus Sampling (CVS), and Percutaneous Umbilical Blood Sampling (PUBS) (also known as Foetal Blood Sampling (FBS)). Alternatively, parents also have the option of choosing not to undergo any prenatal testing for such abnormalities.

5.28 Prenatal testing assures parents of the foetus’s condition, thus giving them information about the possibility of predispositions to certain genetic conditions that might develop in the foetus prior to birth. This allows the parents to decide on the follow-up actions required, such as consulting a specialist doctor for medical advice, consideration for foetal therapy if applicable , and appropriate preparation for the birth of an affected baby. Parents may also choose not to take any further actions and continue pregnancy as usual. Prenatal testing also informs and provides parents with the option for termination of a pregnancy with an affected foetus (i.e., interruption of pregnancy), if necessary.

5.29 However, specific types of prenatal diagnostic testing (e.g., amniocentesis, CVS, PUBS) are invasive and involve inserting a thin catheter or needle either through the abdomen or the cervix to collect samples of amniotic fluid or placental tissue. While dependent on the specific type of test employed, such procedures are generally accompanied by an increased risk of miscarriage and other complications of pregnancy. For instance, the rate of miscarriage with amniocentesis is about

1 in 200, carrying with it a low risk of uterine infection, which could also lead to miscarriage, leakage of amniotic fluid and injury to the foetus. The rate of miscarriage with CVS is approximately less than 1 in every 200, or slightly higher than that of amniocentesis. , FBS), the rate of miscarriage is about 1 to 2 in every 100 procedures, where the test could result in bleeding from the foetal blood sampling site, leaking of amniotic fluid and infection.

While there are tests available such as non-invasive prenatal testing (NIPT) which are non-invasive, these are used primarily for screening purposes and would require confirmatory diagnostic tests. For example, NIPT primarily screens for common chromosomal conditions but is unable to detect genetic or structural abnormalities, or other birth defects. A certain amount of cell-free foetal DNA (cffDNA) is also required in the maternal blood for a test result to be generated.

30 Despite the benefits of prenatal screening testing for parents, results obtained from the tests may not always be reliable. Erroneous results of such tests may lead to the failure to identify birth defects accurately. Prenatal testing can also be expensive, costing anywhere from a few hundred to several thousand dollars, depending on the type of screening or diagnostic test used. , combined first trimester screening) are more affordable than invasive tests such as amniocentesis, CVS and PUBS. It should be noted too that termination of pregnancy is prohibited after 24 weeks of gestation in Singapore, except in the circumstances of a mother’s life being in danger. Therefore, the prenatal diagnosis test must be completed within this window if the parents are considering the option of terminating a pregnancy with an affected foetus. c. Adoption

5.31 Adoption is a legal process in which an individual takes over the parenting of a child from the child’s biological or legal parents. It is a long-term commitment and responsibility for the upbringing of a child, which is distinct from other types of relationships, such as fostering, which is a temporary care arrangement where the foster children remain the legal children of their natural parents.

5.32 Adoption provides couples, who are unable to produce children of their own that are genetically healthy, an opportunity to complete their family. However, the fact remains that these couples do not share a biological link with the adopted child. d. Selective termination of pregnancy

33 Selective termination is used primarily to prevent or reduce complications caused by the birth of an affected foetus(es), particularly in higher-order multiple pregnancies, and increases the survival odds of the remaining foetus(es). , twins, triplets, and higher-order multiples) are often at a higher risk of various maternal, foetal, and neonatal complications, as compared to singleton pregnancies, which attribute to a higher proportion of preterm births. For instance, neurodevelopmental morbidity such as cerebral palsy in twin births or higher-order pregnancies are markedly higher than in singleton births.

Besides multifoetal pregnancy reduction (MPR), which is used to reduce the number of foetuses in the gestation and improve maternal and survival outcomes of the foetus(es), selective termination involves reducing the foetal number by removing the foetus(es) with a known genetic, structural or other abnormality identified during prenatal testing. POTENTIAL RESEARCH AND CLINICAL APPLICATIONS OF HNGE AND CURRENT ESTABLISHED METHODS TO TREAT DISEASES

5.34 However, the procedure is not without risks, such as retained placenta, infection, miscarriage, and pre-labour rupture of membranes. e. Embryo selection 35 During in vitro fertilisation (IVF), multiple embryos are created to increase the likelihood of obtaining a viable embryo. However, the chances of a viable embryo being successfully implanted are subject to various factors including biological variation. Pre-implantation genetic testing for monogenic/single gene defects (PGT-M), preimplantation genetic testing for chromosomal structural rearrangements (PGT-SR) or pre-implantation genetic testing for aneuploidies (PGT-A) are used to test and diagnose embryos for specific genetic or chromosomal abnormalities.

The embryo that is not affected with the genetic dysfunctionality tested for will be selected and implanted into the woman’s uterus to maximise the chance of successful and normal pregnancy. Hence, PGT-M/SR/A reduces the risk of passing on inherited conditions or genetic disorders and allows couples to avoid an abnormal pregnancy.

5.36 Unlike gene editing, which may cause unintentional mutation(s) to be passed down to future offspring, embryo selection is deemed to be safer as PGT-M/SR/A does not cause genetic aberrations in the embryo, while enabling couples to have a genetically identical child but without the inherited genetic disorder. However, embryo selection is limited and may not be a feasible option in situations where all or a majority of embryos are affected by genetic dysfunctionality. This is relevant in the case of Huntington’s disease, where all embryos would carry the dominant disease-causing allele. In polygenic conditions, caused by the combination of two different mutations in a gene, and combinations of specific alleles of two or more genes, it may be challenging to select embryos by PGT-M/SR/A and thus render limited use. f. Donated gametes

5.37 Use of donated gametes may be helpful particularly in cases where the couple’s sperms and/or eggs are not healthy enough to produce a successful pregnancy, or when one or both parents are affected by genetic condition(s), which may prevent or impair the birth of the child.

5.38 Using donated eggs or sperms allows one of the intended parents to maintain the genetic relationship with the child, while avoiding the propagation of any inherited condition that may be passed down to the child. Furthermore, the procedures involved (i.e., intrauterine insemination and IVF) are simple, safe, and carry a low risk of serious complications. However, unlike donated eggs or sperms, using donated embryos from others does not allow either of the intended parents to have children that are genetically associated with them. g. Intrauterine foetal gene therapy

5.39 Gene editing technology may be used to treat monogenic disorders in foetus(es) via intrauterine foetal gene therapy. The procedure involves injecting the therapeutic agent (e.g., vectors encoding therapeutic genes) into an umbilical blood vessel, the amniotic fluid, or occasionally directly into foetal tissue, with the guidance of an ultrasound probe. While intrauterine foetal gene therapy is not currently available for clinical use, it might yet become an alternative to heritable gene editing for fertility issues in the future.

5.40 Foetal gene therapy can be employed to treat monogenic disorders prior to the pathological development of the disease, thus significantly decreasing morbidity and mortality. Unlike heritable gene editing, foetal gene therapy has the advantage of robust preclinical data. Several clinical trials in animal models have shown that viral vectors are efficient vehicles in foetal gene therapy, thus making foetal gene therapy a promising alternative to heritable gene editing. However, as with other genetic modifying technologies, foetal gene therapy may cause insertional mutagenesis, oncogenesis, genetic mutation transfer from mother to child and foetal disruption.

5.41 The applications of HNGE stretch across various indications and may be used in investigative studies of diseases, enhancement of specific traits, therapeutic intervention, diagnosis of diseases as well as treatment of fertility. However, many findings reported by the many aforementioned research groups are largely preliminary and warrant further studies to determine the long-term safety and efficacy of gene editing technologies. Studies of the differences in idiosyncratic effects due to individual genetic variations should also be taken into consideration. Therefore, until the safety and efficacy of HNGE technology are demonstrated in pre-clinical studies and in clinical trials approved under regulated clinical trial frameworks, the current established methods would be preferable for treating or preventing diseases in individuals and their offsprings.

MOSAICISM, OFF-TARGET EFFECTS, AND ON-TARGET UNDESIRABLE MODIFICATIONS 1 Targeted modifications to nuclear DNA and gene editing technology offer the potential to prevent, treat or even cure certain inherited genetic disorders, and might even be used to enhance traits and confer resistance to diseases. When used in a controlled manner, corrections to the genomic sequence could be carried out with precision using molecular scissors, which are mostly enzyme-based, to rectify or remove mutations that could otherwise lead to deleterious health conditions.

Yet these technologies could also lead to unintended biological outcomes such as chromosomal mosaicism in embryos and undesirable consequences arising from off-target mutations and deletions. This chapter discusses the ethical principles of proportionality, sustainability, solidarity and responsible stewardship of science, the ethical issues of chromosomal mosaicism, off-target effects and on-target undesirable modifications, and their impact on individuals and society as a whole, which would be important considerations for potential applications of HNGE.

2 Chromosomal mosaicism is a condition that occurs when a person has two or more sets of cells that are genetically different from one another. For example, a person with this condition might possess some cells that have 46 chromosomes and others that have 47 chromosomes. , after significant DNA replication and cell division take place) and can lead to genetic disease if the abnormal cells begin to outnumber the normal cells, thereby undermining disease prevention.

With technological improvements and better understanding of gene editing mechanisms, chromosomal mosaicism in embryos could be reduced with more precise modifications or adjustments in dosage regimens. However, with current technology, it remains highly possible that chromosomal mosaicism in embryos could lead to preimplantation embryo wastage, miscarriages and an increased risk of birth disorders and genetic diseases as there is currently no non-destructive way of determining whether all the cells in the embryo carry exactly the same edits.

Physiological defects arising from the genetic aberrations could potentially be passed on to future generations, who may then be afflicted by severe genetic diseases that could prove more fatal than

the initial benign condition that was meant to be treated by the genetic modification. Therefore, researchers are advised to consider the following ethical principles when conducting heritable genome editing for the treatment of diseases, conferring resistance, enhancement of traits or for infertility (for both clinical research and clinical applications, if permitted in the future): a. Proportionality

3 The principle of proportionality requires that researchers ensure the risks of HNGE biomedical research and clinical applications are not disproportionate to their benefits by minimising the harm to individuals and future offspring while maximising benefits using heritable gene editing technology for treatment of diseases, conferring resistance, enhancement of traits or for the treatment of infertility.

Given a dearth of sufficient safety and efficacy data for interventions employing heritable gene editing, the occurrence of chromosomal mosaicism as a result of inaccuracy or imprecision in such techniques could pose harm to the individual receiving the treatment. This could outweigh the benefits of the therapy. , correction of mutations in germ cells that could possibly treat infertility to enable pregnancy). The risk of miscarriage could be attributed to abnormalities in the chromosomes which occur because of aberrant cell division and growth.

Miscarriages might also lead to further complications such as psychological distress and future risk of infertility for the expectant mother. Therefore, heritable gene editing for treatment of diseases, conferring resistance, enhancement of traits or for infertility (in both clinical research and clinical applications) should be considered only if scientific and technological advancements are able to reduce mosaicism or mitigate its effects. b. Sustainability

4 The principle of sustainability provides that the use of HNGE in biomedical research and clinical applications should not harm the offspring and their future generations. Given that the use of gene editing technology may result in chromosomal mosaicism, implanting or transferring mosaic embryos could lead to an increased risk for a child to be born with a chromosome disorder, thus potentially compromising the welfare of the offspring.

While more than 100 live births have been documented with reassuring outcomes and no abnormal phenotype after mosaic embryo transfer, there are questions that remain unanswered, such as the long-term outcomes of infants born via mosaic embryo transfer. Therefore, it is important to validate the long-term safety and efficacy of gene editing technology before it is used for clinical research and applications involving heritable gene editing. Further in vitro research on embryos or gamete precursors is also required to fully understand the implications of heritable gene editing technology.

MOSAICISM, OFF-TARGET EFFECTS, AND ON-TARGET UNDESIRABLE MODIFICATIONS c. Solidarity 5 The principle of solidarity asserts that benefits harnessed through research and from applications of HNGE, supported by individuals’ altruistic participation, should extend to wider society and that risks should be minimised. Given that heritable gene editing for the treatment of diseases, conferring resistance, enhancement of traits or for infertility, carry the risks of chromosomal mosaicism and miscarriages, research participants and individuals undergoing such procedures may be exposed to harm that could also affect future generations.

The principle of solidarity and mindfulness of the public good deserve greater consideration in ensuring that advances in HNGE become shared benefits. Hence, heritable gene editing should not be conducted for clinical research and clinical applications until they are proven safe and beneficial to the research participants and wider society. Until then, current established methods of treatment or prevention of diseases described in Chapter 5 would be recommended and clinicians should ensure that patients’ expectations are realistic. Issue 2: Off-target mutations, deletions, and rearrangements in DNA

6 While HNGE introduces desired changes at the intended target sequence, unintended modifications could be introduced elsewhere in the genome and are known as off-target effects. Off-target changes arising from gene editing can include unintended mutations, insertions or deletions in the genome, which may result in varying consequences depending on the location and nature of the change. These can range from benign effects to harmful disruptions of critical genes or regulatory regions of the genes, and which may result in unintended consequences for the health of individuals.

Advancements in recent years have improved our ability to reduce the frequency of unwanted changes as well as to detect off-target mutations when they occur. 01 percent at individual atrisk sites have been achieved in some cases. However, current tools in gene editing (both heritable and non-heritable) still harbour the risk of causing DNA deletions and rearrangements that might eventually lead to genome instability and disruption of the functional genes. As such, this may result in aberrant cell cycles and unprecedented changes in gene expression and regulation.

The risk of further complications, such as the development of cancer and allergic reactions, would be dependent on the type Consideration: The above issue may not be applicable to embryos that would not have existed if gene editing was not performed, or to embryos that were affected by genetic mutations leading to catastrophic conditions. The risk of mosaicism may not outweigh the risks involved if the embryos do not undergo gene editing, and therefore heritable gene editing may be attempted for such cases. of gene editing approach employed, as well as the adverse reactions associated with the modality. Therefore, researchers are advised to consider the following ethical principles when conducting non-heritable and heritable gene editing (if permitted in the future) for clinical research and clinical applications:

a. Proportionality 7 The principle of proportionality provides that the risks of biomedical research and clinical applications involving HNGE are not disproportionate to their benefits by minimising the harm to individuals and their future offspring while maximising the benefits. While modern gene editing tools may alleviate some safety concerns due to the targeted nature of the technology, other concerns persist, such as the potential for off-target effects that could impair a healthy gene function and thus compromise the health and wellbeing of patients undergoing clinical trials of non-heritable gene editing.

Undesirable consequences such as these could outweigh the benefits of nonheritable gene editing, for instance, in the correction of disease-causing mutations. Researchers and clinicians are thus obligated to ensure a favourable risk-benefit ratio for patients undergoing HNGE clinical trials and should ensure that clinical trials of non-heritable gene editing are designed to minimise any unprecedented harmful effects to patients. However, this would be challenging to achieve in the short-term, given the lack of understanding of the extent to which non-heritable gene editing can cause unintended secondary edits in the target genome.

Therefore, it is essential to conduct further studies of non-heritable gene editing to fully understand the unintended consequences of HNGE. , guidelines and oversight committees) to assess the benefits of gene editing technology vis-à-vis the risks associated with mosaicism and off-target effects. b. Sustainability

8 The principle of sustainability holds that biomedical research and clinical applications involving HNGE must ensure that adverse effects or harm rendered by the use of the technology are not perpetuated to future generations. Although heritable gene editing offers promise in preventing and treating debilitating inherited diseases, and enabling infertile couples to conceive children, a study at Oregon Health and Science University has revealed that gene editing to correct disease-causing mutations in early human embryos could lead to unintended and potentially harmful changes in the genome.

This unintended effect could be passed on to future offspring and jeopardise their wellbeing. In another research study, scientists at Columbia University, seeking to fix defective DNA in human embryos using CRISPR-Cas9, discovered that the editing caused unintended changes, such as loss of an entire chromosome in more than MOSAICISM, OFF-TARGET EFFECTS, AND ON-TARGET UNDESIRABLE MODIFICATIONS

half of the embryos experimented on. These changes could be passed on to future generations if the embryos are used to establish pregnancy, indicating that it is too early to know whether heritable gene editing can be conducted safely. Therefore, more research would need to be conducted to develop ways of mitigating off-target effects and other unintended mutations as a result of heritable gene editing on human embryos before gene-editing established pregnancy can be considered safe. For example, researchers can aim to enhance the precision of gene editing technology with high fidelity variants or platforms to minimise any off-target effects.

c. Responsible stewardship of science 9 The principle of responsible stewardship of science refers to the moral requirement incumbent upon researchers to be prudent about resources utilised in the pursuit of HNGE research and to observe ethical guidelines governing its application. This includes setting research priorities while considering the needs of society so that social and scientific benefits are maximised and potential risks are minimised. Researchers have been developing strategies to prevent or reduce the occurrence of known errors arising from HNGE.

For instance, gene editing tools that have greater precision, such as base editors, have been investigated in preclinical disease models to determine their editing efficiencies and accuracy. Patients undergoing gene editing interventions should understand the intervention and be made fully aware of the potential risks prior to receiving the treatment, while their informed consent should be obtained prior to the procedure.

10 Regulatory bodies should establish guidelines for the information that must be included in informed consent for researchers and research institutions to refer to, to ensure that all required information on the gene editing intervention is made known to the patient or participant. Due to the complexity of gene editing technology, patients may not fully understand all its aspects. Therefore, researchers and clinicians should ensure that patients are sufficiently informed and understand the potential benefits and risks involved.

Researchers and clinicians should also obtain the patient’s consent and ensure their safety by continually engaging the patient for follow-up and having further discussion should new information relating to the intervention arise. As off-target effects can now be sensitively and comprehensively quantified, patients should be informed of these risks, including their likelihood and severity (from low to extremely high severity) during genetic consultation. , parents or next of kin) in accordance with the Singapore Medical Council (SMC) Ethical Code and Ethical Guidelines and the Mental Capacity Act 2008.

For non-heritable gene editing research involving patients with diminished or no capacity, researchers should obtain valid informed consent from legally authorised persons in compliance with the Human Biomedical Research Act 2015.

6.11 Additionally, researchers and clinicians conducting research and clinical applications involving HNGE technology should be appropriately trained to accurately assess the potential benefits and risks of gene editing interventions. This may include training in genetics, the field of genomics and gene editing technology. Researchers and clinicians should also be appropriately trained in relevant topics in ethics, law and sociology so as to be fully equipped with skills and knowledge to consider the potential risks and implications for patients and future generations, and conduct appropriate counselling for patients and obtain their informed consent. There should also be institutional oversight to ensure continuous training of researchers and clinicians involved in HNGE technology.

12 It has been widely expected that HNGE will help to significantly advance medicine, given its potential to offer novel methods of curing diseases, enhancing traits, conferring resistance and treating infertility. However, the technology is currently at a nascent stage, lacking sufficient safety and efficacy data. Therefore, the potential risks associated with gene editing technology largely outweigh the perceived benefits—an imbalance that essentially compromises the principle of proportionality.

Given the current understanding of gene editing tools, it would be difficult to be confident that future generations of individuals receiving the treatment would be free of harm, which then also clouds the principles of sustainability and solidarity. Nevertheless, research in HNGE has continued to improve the precision of gene editing technology, thus ensuring responsible stewardship of science. SAFETY AND LONG-TERM EFFECTS OF HNGE

7.1 Gene editing offers new ways of treating diseases and may potentially be used for enhancement of human performance. However, gene editing has yet to receive unequivocal acceptance for widespread use in the clinic. This is because the technology is still in early development, which raises concerns about its safety and unknown longterm side effects of the technology on individuals receiving the treatment. This chapter discusses the ethical principles of proportionality, sustainability, and responsible stewardship of science, the ethical issues of long-term side effects and consequences of non-heritable and heritable gene editing, and recommendations for managing these consequences. Issue 1: Possibility of long-term repercussions following non-heritable gene editing

2 Since the development of CRISPR as a tool for gene editing, several therapeutics involving this technology are currently being evaluated in non-heritable gene editing clinical trials and have been approved for use. Among those that have been conferred with the Regenerative Medicine Advanced Therapy (RMAT) designation by the FDA for accelerated approval are exagamglogene autotemcel (exa-cel) for sickle cell disease (SCD) and transfusion-dependent beta thalassaemia (TDT).

This same treatment was approved in the UK, where it is sold under the brand name ‘Casgevy’, and is meant to prevent episodes of excruciating pain that are associated with sickle cell disease, thus freeing those suffering with beta thalassaemia from regular blood transfusions. Another treatment that has received accelerated approval by the FDA is CRISPR-modified chimeric antigen receptor T (CAR-T) cells, which target cancer cells for leukaemia and lymphoma, bringing hope to afflicted patients who would otherwise lack effective treatment options.

7.3 While clinical trials for non-heritable gene editing may lead to the development of new solutions to treat complex genetic diseases in the future, the long-term safety and stability of non-heritable gene editing have not as yet been adequately addressed, even in preclinical studies. As such, unforeseeable repercussions could surface years after patients received treatment from non-heritable gene editing clinical trials and may result in undesirable biological consequences or side effects. For instance,

off-target modifications resulting from the treatment of gene editing could trigger activation of cancer-causing genes and thus compromise the health of patients in the long term. Therefore, researchers are advised to consider the following ethical principles when conducting non-heritable gene editing for biomedical research and clinical applications: a. Proportionality

, a favourable risk-benefit ratio). While clinical trials and clinical applications involving non-heritable gene editing can benefit research participants and patients by allowing them to correct mutations that cause underlying diseases, the potential harmful side effects and long-term consequences might outweigh the benefits.

Hence, principal investigators of HNGE clinical trials, as well as clinicians providing treatment involving non-heritable gene editing, need to ensure that the risks are not disproportionate to the anticipated benefits by maximising the potential benefits while maintaining a favourable risk-benefit ratio for clinical trial participants and patients. Researchers, research institutions and clinicians should ensure that the risks of any unintended consequences from non-heritable gene editing interventions becoming heritable are reduced, and that these risks be documented and assessed appropriately. b. Responsible stewardship of science

5 The principle of responsible stewardship of science refers to the moral requirement of researchers to be prudent about the resources utilised in the pursuit of HNGE research and to consider the ethical guidelines governing applications of non-heritable gene editing. Given the as yet largely unknown long-term effects of gene editing technology, it would be difficult to predict and avoid consequences that clinical trial patients may face in the future. Hence, conducting such clinical trials may expose patients to possible long-term ramifications in the future despite achieving short term benefits.

Appropriate measures, such as establishing guidelines for evaluating off-target effects and risk-benefit assessments, should be taken by researchers to anticipate and/or manage uncertainties and long-term consequences associated with non-heritable gene editing in order to ensure responsible stewardship of science. The risk-benefit assessments should be presented clearly to patients and participants to ensure that they understand and are fully informed of the potential benefits and risks.

Furthermore, researchers, research institutions and clinicians should continuously review whether existing regulations and guidelines are capable of managing the risks and benefits of HNGE. SAFETY AND LONG-TERM EFFECTS OF HNGE 6 Given that the long-term safety of non-heritable gene editing has not been fully established, it is essential that researchers and physicians conduct long-term follow-up on all patients and participants in clinical trials evaluating new therapeutic modalities for non-heritable gene editing. This will allow them to monitor adverse developments and evaluate the risks and benefits, which would aid in mitigating the risk of any delayed adverse development occurring due to the treatment.

For instance, four out of nine patients successfully treated in a clinical study investigating the use of gene therapy for severe combined immunodeficiency (SCID) were found to develop leukaemia even as long as 68 months after gene therapy. In addition, the FDA updated the guidelines in 2020 on the design of long-term follow-up studies for the collection of data on delayed adverse events following the administration of a gene therapy product. This suggests that studies using gene editing products should follow up with patients for at least 15 years, and highlights the importance of long-term follow-up.

Nonetheless, it should be noted that such long-term monitoring of patients after the trial faces some technical and ethical challenges: a. Experimental approaches commonly employed in clinical trials such as randomised controlled trials are seldom suitable for long-term monitoring. This is because subjects randomly assigned to a particular treatment regimen for prolonged periods (e.g., five years or longer) or into a placebo group, may choose to opt out of the study in the event that a better treatment becomes available, or may decide to switch therapy for other reasons, such as poor prognosis or treatment-related side effects.

b. The use of a placebo may become less ethical and relevant for trials of a lengthy duration, especially in situations where patients with dilapidating conditions, such as cardiovascular diseases or cancer, are placed in the placebo control group. Clinical trials performed over a longer duration also necessitate an open label study design where both researchers and participants are aware of the treatment being administered.

, without a placebo group), with all participants receiving the same treatment if there is no standard of care, which might then reap results that are insufficient in terms of establishing the efficacy of the intervention. Notwithstanding these challenges, an open label study or an uncontrolled trial may be considered more ethical compared to the use of placebo, as patients are not denied any treatment, which may prevent or delay death or other major consequences from the disease. c. As the duration of a study increases, the number of research participants may decline.

It was reported that one in four participants drop out on average, citing reasons such as fear of side effects, study procedures, inconvenient location and lack of support from family. , loss of follow-up), thus undermining the reliability and validity of efficacy studies for the non-heritable gene editing treatment. d. It is important to ensure that study protocols for long-term monitoring of HNGE are comprehensive and address the potential ethical challenges posed by invasive procedures for obtaining samples for such long-term studies.

For example, bone marrow biopsies, direct sequence testing or other invasive methods meant to assess the long-term effects of gene editing, could result in undue physical and psychological burdens on patients. Therefore, researchers need to carefully weigh the invasiveness of procedures against the importance of the data being gathered. Devising non-invasive alternatives or minimising the frequency of invasive sampling could be necessary to protect patient wellbeing, while also ensuring robust data collection.

Issue 2: Difficulty in predicting how the gene alterations as a result of heritable gene editing interact with genetic variants and the environment, and the subsequent side effects 7.7 Compared to non-heritable gene editing, the clinical research and clinical applications of heritable gene editing raise significantly more concerns about the safety and longterm consequences of its use. While heritable gene editing may prove to be useful in eradicating genetic diseases, especially in children at birth by precisely correcting the genetic sequence, there is a likelihood of creating permanent unintended changes that could be passed down to future generations. Such modifications made to the genome may invoke unprecedented biological consequences, including disrupting inherent protection from infection as well as activation of genes with harmful effects.

8 Mutations introduced to genes may interact with inherent gene variants present within an individual and render unprecedented biological outcomes. Inherent gene variants are changes in a person’s DNA sequence which exist prior to gene editing and can be inherited or non-inherited. Inherited variants, also known as germline variants, are passed down from parent to child and are present throughout a person’s life.

Non-inherited variants occur at some point during a person’s life and may manifest themselves during natural cellular processes such as cell division, or due to environmental factors such as exposure to ultraviolet radiation from the sun or smoking. While heritable gene editing can present prospective parents with the opportunity to have a biological child without passing on a genetically-heritable disease, the current technology is still unable to predict how these exogenous genetic alterations might interact with existing gene variants within the child.

The difficulty in anticipating, and in turn, mitigating possible side effects arising from the intrinsic SAFETY AND LONG-TERM EFFECTS OF HNGE genetic interaction as well as that with the environment, could expose future offspring to lethal long-term ramifications. Furthermore, the lack of studies on the side effects of gene editing on intrinsic gene-gene interaction and the environment underlines the unpredictability of the long-term consequences of the technology.

9 The inability to predict the undesirable outcomes and consequences of heritable gene editing could be attributed to the fact that control experiments are performed only on small groups of cells. The current ability to perform quality control experiments only on a subset of cells means that the precise effects of genetic modification on an embryo may be impossible to predict until after the child is born. In some cases, potential problems and side effects may not surface until years after the child is born, making it difficult to predict the side effects of heritable gene editing. Wei and Nielsen reported in their study in 2019 that CCR5Δ32 homozygote carriers in the UK Biobank were shown to suffer from a 21% increase in their mortality rate. The CCR5 gene has been widely shown to play a part in the human immune system.

While the loss of its function may be protective against diseases such as multiple sclerosis, spontaneous hepatitis C viral clearance, chronic and aggressive periodontitis as well as confer resistance against HIV-1 infection, the authors of this study postulated that the Δ32 mutation could be highly pleiotropic and likely increase susceptibility of an individual with the mutation to develop other common diseases.

7.10 Given the aforementioned considerations, researchers are advised to consider the following ethical principles when conducting heritable gene editing for clinical research and clinical applications (if permitted): a. Responsible stewardship of science

11 The principle of responsible stewardship of science requires researchers to be committed to ensuring that scientific knowledge, data, processes, and know-how around gene editing technology are put to good use not only to improve health outcomes, but also to acknowledge the difficulties and uncertainties alongside the benefits of heritable gene editing for clinical applications (if permitted in the future). Researchers also have an obligation to minimise potential risks to individuals and their future offspring associated with gene editing intervention.

With the current lack of long-term safety and efficacy data on gene editing technology, the use of heritable gene editing is currently deemed unsafe for future offspring with long-term implications, where possible exposure to serious side effects may be fatal for future offspring. The use of heritable gene editing can only be considered safe for clinical research and clinical applications following further research studies that prove the safety and efficacy of gene editing technology. b. Sustainability

7.12 The principle of sustainability provides that research and applications of HNGE should ensure that the adverse effects or harm rendered by gene editing technology are not passed down to future generations. Given that the long-term consequences of the heritable gene editing cannot be predicted or mitigated until the birth of the genetically modified child, clinical research and clinical applications involving heritable gene editing would infringe the principle of sustainability, as the welfare of the offspring and future generations would likely become compromised when exposed to serious side effects.

13 Intergenerational monitoring, which refers to long-term follow-up studies of research participants and their descendants, could help researchers determine the long-term side effects of heritable gene editing on the individual that may be subsequently passed on to future generations and also help assess its safety and efficacy for clinical use. One example of intergenerational monitoring in biomedical research is the Framingham Heart Study of the natural history, risk factors and prognosis of cardiovascular, lung and other diseases.

This study began recruitment of research subjects in 1948, before enrolling the second and third generations of the original subjects in 1971 and 2002, respectively. The follow-up studies included clinical and laboratory assessments of cardiac structure and function. However, intergenerational monitoring in clinical trials, much like other procedures in biomedical research, poses the primary ethical challenge with respect to a person’s right to autonomy and privacy:

a. Personal and medical information of subjects involved in intergenerational monitoring have to be collected with the appropriate consent of the participants. However, the descendants of a child conceived from an edited embryo in a clinical trial may invoke a limited waiver of privacy during occasions requiring the management of risks associated with heritable gene editing and communication of any adverse findings with recipients of intergenerational monitoring. The waiver could apply to certain key aspects of the child’s life as well as their descendants, which could raise difficult issues involving informed consent: the reason being that parents are unable to provide consent that binds their children past the legal age when the children can exercise their own judgement and decide whether to continue as participants of the study, as this would violate their autonomy.

7.14 In view of the ethical consideration outlined above, patients could opt for PGT as an alternative procedure to heritable gene editing for clinical applications (if permitted) to ensure their children do not inherit their own genetic conditions. While not a curative therapy, PGT could ensure that future offspring are not affected by this genetic condition by evaluating embryos for specific genetic conditions (see Chapter 5 for alternatives to HNGE). Consideration: Issue 2 may not be applicable to embryos that would not have existed if gene editing was not performed/embryos that were affected by genetic mutations that lead to catastrophic conditions. The risk of possible side effects may not outweigh the risks involved when the embryos do not undergo gene editing, and therefore heritable gene editing may be attempted for such cases, if permitted. SAFETY AND LONG-TERM EFFECTS OF HNGE

Issue 3: Lack of sufficient safety and efficacy data for the use of heritable gene editing for infertility 15 Heritable gene editing presents as a possible infertility treatment for individuals with fertility issues, through unravelling of underlying genetic causes as well as modifying the genes associated with infertility in germ cells. For example, CRISPR-Cas9 technology is used to identify and study potential infertility mutations, by modelling infertility-causing mutations in mice and evaluating whether the human mutation renders the mice infertile. For example, researchers have been using the CRISPR- Cas9 system to produce mice that lack testis-specific genes, with studies revealing that several genes are indispensable for male fecundity.

However, preclinical studies have yet to establish the safety of such gene editing technology for humans, or even in human and mammalian models other than mice. Hence, heritable gene editing is still considered to be unsafe for clinical research and clinical applications to treat male or female infertility, as they can be exposed to unwanted side effects such as mutagenesis.

For example, while studies have shown that gene therapy involving viral vectors could correct spermatogenesis in infertile mice, there are major concerns pertaining to translating these studies to clinical applications, such as insertional mutagenesis, cell-specific targeting and pronounced inflammation. a. Proportionality

7.16 The principle of proportionality requires that researchers ensure risks of heritable gene editing for infertility are not disproportionate to the benefits by minimising the harm to individuals and future offspring. Given the lack of safety data on current gene editing technology for the treatment of human infertility, clinical research and applications could harm the individuals undergoing the treatment and might outweigh the benefits of helping prospective parents conceive. Infertile couples are recommended to address their fertility problems through safer alternatives, such as medicines, surgical procedures and assisted reproduction technology such as IVF procedures, until the efficacy of gene editing for infertility is well established (see Chapter 5 for alternatives to HNGE).

17 Heritable gene editing could contribute to the reduction or even elimination of some serious inherited diseases within a population. However, variants associated with disease might also be associated with other beneficial characteristics, which would then also be lost and might be important for survival. For example, the Chinese scientist, He Jiankui, disabled the C-C chemokine receptor 5 (CCR5) gene to confer resistance to HIV in human embryos, resulting in the birth of twin girls.

However, a mouse experiment published in 2005 showed that CCR5 promotes trafficking of important immune cells to the brain during the infection with West Nile Virus. It was also found that humans who lack this protein are more susceptible to severe encephalitis and even death compared to others when infected with West Nile Virus. Therefore, the gene-edited babies created as a result of He’s experiment may be resistant to HIV but may be more susceptible to certain viral infections in the future.

Hence, researchers and research institutions are advised to consider the following ethical principles when considering applications of heritable gene editing if permitted in the future: a. Proportionality 18 The principle of proportionality requires that risks of research and clinical applications involving gene editing technology are not disproportionate to their benefits by minimising harm while maximising benefits to individuals and future offspring. It is incumbent upon researchers to reduce potential harm, or limit to reasonable risks, to individuals and their future offspring, while also maximising benefits as a result of gene editing intervention.

Applications of heritable gene editing to confer resistance to a particular disease could, unknowingly, harm future offsprings by removing beneficial characteristics associated with that disease that may be vital for survival or integral to good health. , to be resistant to a particular disease).

7.19 Hence, while non-heritable and heritable gene editing hold tremendous promise in addressing genetic disorders and advancing medical science, their long-term safety and efficacy remain a paramount concern. These safety and ethical issues demand a cautious and well-regulated approach to ensure responsible application of gene editing technology until these concerns are addressed in the future. Rigorous research, ongoing monitoring and clear ethical guidelines are essential to mitigate risks and uphold the wellbeing of individuals. It would be important too, to weigh the potential benefits from the advancements in HNGE against the risks as well as ethical considerations to ensure the long-term safety and efficacy of the technology. PROCUREMENT AND USE OF HUMAN EMBRYOS AND OOCYTES IN HNGE RESEARCH

1 Human embryos have been used by researchers in gene editing as a means of expanding our knowledge base of the human gene function and early embryonic development, as well as to advance research on infertility, genetic diseases and intractable diseases. In 2015, the first case of gene editing in early-stage human embryos was reported in China, where CRISPR was employed to edit the human beta-globin gene associated with beta-thalassaemia. The use of embryos in gene editing research, however, raises several ethical issues.

This chapter provides an overview of the 14-day limit for embryo research and the different types of embryos used in HNGE research. Furthermore, the chapter also discusses the panoply of ethical issues involved in the procurement and use of embryos and oocytes in gene editing research, the application of relevant ethical principles of respect for persons, justice, proportionality, and transparency, and recommendations for managing each of these ethical issues.

8.2 The BAC, in its ‘Ethics Guidelines for Human Biomedical Research (2021 revised edition)’, recommends against developing human embryos for research after the 14th day.

8.3 The 14-day rule was first proposed by the Ethics Advisory Board of the US Department of Health, Education, and Welfare and later endorsed by the Warnock Committee in the UK. It is used in science policy and regulation to limit research, including gene editing research, on human embryos to a maximum period of 14 days after their creation or to the equivalent stage of development that is normally attributed to a 14-day-old embryo. The placing of the boundary at 14 days can be attributed to the primitive streak that appears after the 14th day of human embryo development, signalling the onset of cell differentiation and growth of organs including the nervous system. This rule has been highly influential and is one that has been adopted by many countries to facilitate ethical research on embryos.

8.4 While it was not possible to culture human embryos in vitro for 14 days when the rule was first implemented, scientific advancements are increasingly making maintaining physiologically normal embryos in culture beyond 14 days a foreseeable reality.

Hence, there has been continuing pressure to modify the rule. For example, many UK scientists are now calling for the current 14-day limit on embryo research to be doubled to 28 days, so that they can study the unexplored areas of early human development. Such a change could yield major scientific breakthroughs for infertility, miscarriage and birth defects.

8.5 However, given that culturing embryos for up to 14 days only became possible in 2016, research into embryos between 7 and 14 days is still in its early stages. In addition, most discoveries to date have been within the first seven days, where researchers have been using gene editing technology to reveal the role of key genes in human embryos in the first few days of development. Hence, it might be premature to consider an extension of the 14-day limit. Accordingly, the BAC’s position on this issue remains unchanged, even for gene editing research.

8.6 The different types of embryos used in gene editing research can be distinguished based on their source: a. Surplus embryos left over from clinical IVF procedures where couples could choose to save the embryos for subsequent cycles in the treatment or donate them to research or to other couples with fertility difficulties ; b. Embryos created specifically for the purpose of research using gametes procured specifically for research on specific gene mutations or profiles.

8.7 The BAC, in its ‘Ethics Guidelines for Human Biomedical Research 2021’, recommended that the creation of human embryos solely for research purposes in Singapore can be justified only when there is strong scientific merit and potential benefits to be had from such research. However, the Human Biomedical Research (Restricted Research) Regulations 2017 allow only surplus embryos created in assisted reproduction treatment to be used for biomedical research, pursuant to IRB approval. This effectively prohibits the creation of embryos for research purposes, even when there is strong scientific merit and potential benefit. Hence, there may be a need for the regulatory authority to review current regulations for restricted research to enable further advancements in biomedical research, including gene editing research.

8.8 The BAC’s position on the use of oocytes or embryos in biomedical research is that specific and personal consent from the donors must be obtained before any oocyte or embryo can be used for this research. The potential donors should be afforded sufficient information and time to make an informed decision. In particular, consent PROCUREMENT AND USE OF HUMAN EMBRYOS AND OOCYTES IN HNGE RESEARCH

for donation of surplus oocytes or embryos should be kept separate from the consent for treatment of women undergoing fertility treatments. Further, the researcher seeking consent for the donation of eggs and embryos for research should not be the physician administering the fertility treatment. The BAC also asserts that women who intend to donate eggs specifically for research (i.e., those who are not undergoing fertility treatment) must be interviewed by an independent panel, given that the process of donating eggs for research is time-consuming, invasive and associated with a certain degree of discomfort and risk. The panel must be satisfied that the women are of sound mind, understand the nature and consequences of their donation and have freely given explicit consent, without any inducement, coercion or undue influence.

8.9 While surplus embryos from IVF are commonly used by researchers in various countries for gene editing research, the availability of gametes with desired genotypes or genetic profiles may be limited. If a scientist becomes interested in studying gene mutations in oocytes for a given disease-causing gene, or to correct a specific gene mutation, it is essential that oocytes obtained possess the desired genotype. Researchers may have to procure oocytes from women for such oocyte gene editing research, which raises ethical issues as described below. Issue 1: Risks involved in the procurement of human oocytes for HNGE research

10 The invasiveness of the medical procedures involved in procuring oocytes entails some risk to donors. A woman would have to undergo stimulation of her ovaries through multiple hormone injections. Thereafter, the oocytes are collected under mild anaesthesia via a special needle that is attached to an ultrasound vaginal probe. Such ovarian stimulation carries some health risks as the process can lead to ovarian hyperstimulation, a condition in which the ovaries become swollen and painful because of receiving shots of fertility medicines to trigger ovulation. The condition may even be life-threatening if severe, although such cases are rare.

This very risk to donors was observed in a study to correct a heterozygous MYBPC3 mutation, which causes hypertrophic cardiomyopathy, in human preimplantation embryos using CRISPR-Cas9 editing. In this study, oocytes had to be procured from healthy donors, which were subsequently fertilised by sperm carrying the mutation. The consent forms provided to these healthy donors mentioned the risk of ‘death’ three times in the context of different procedures, highlighting the significant risks inherent in oocyte procurement from healthy donors. Other potential risks could also be psychological in nature, including anxiety, mood swings and post-donation adjustment.

8.11 The scarcity of human embryos and gametes, particularly oocytes that are available for biomedical research, gives rise to various concerns, including the risk of exploitation through commercialisation of eggs as an unintended consequence of substantial compensation amounting to an inducement. This situation could risk undermining the autonomy of the donors (e.g. such as to take undue risks against their better judgment). Healthy women who volunteer to donate oocytes specifically for research incur a loss of their time and earnings. However, in such cases, it would be difficult to determine a level of compensation that would not amount to undue influence or inducement, as this would depend on various factors, such as the financial status of the women concerned. Therefore, caution must be taken to ensure that no one is exploited.

8.12 Given these considerations, researchers are advised to consider the following ethical principles when procuring oocytes for the purpose of HNGE research on specific gene mutations: a. Respect for persons 13 The principle of respect for persons maintains that individuals participating in HNGE research are respected as human beings and treated accordingly, including respect for their rights to make their own decisions and ensuring that their welfare and interests are protected. It is important for women to be fully informed of the risks involved and given sufficient time to express consent prior to undergoing oocyte procurement procedures for gene editing research, so that their autonomy is not compromised.

It is also important that there are safeguards to protect oocyte donors and to ensure that there is no coercion or undue influence on their decision. For example, Singapore’s Human Cloning and Other Prohibited Practices Act 2004 prohibits the offering of valuable consideration for the supply of any human egg, human sperm or human embryo, to avoid commodification of oocytes or embryos, and to ensure that donation remains an act of altruism, made without inducement. The Act does, however, allow for the reimbursement of any reasonable expenses incurred by a donor in relation to the supply of human egg, human sperm or human embryo. b. Justice

14 The principle of justice implies the need to equitably reciprocate individuals’ contributions to HNGE research, and that researchers and their institutions shoulder some degree of responsibility for the welfare of participants in the event of adverse outcomes arising directly from their participation in HNGE research.

Based on this principle, the BAC, in its ‘Donation of Human Eggs for Research’ advisory report, recommends that women should be compensated for loss of time and earnings as a result of the procedures required to obtain the eggs, albeit only if the eggs were procured specifically for research purposes and not as a result of clinical treatment. Such compensation should be in addition to any reimbursement of expenses incurred and should not be dependent on the quantity nor the quality of the eggs obtained, as that does not represent payment for the eggs. This is also applicable for gene editing research in embryos or germline cells.

Nonetheless, given that Singapore’s Human Cloning and Other Prohibited Practices Act allows only for reimbursement of PROCUREMENT AND USE OF HUMAN EMBRYOS AND OOCYTES IN HNGE RESEARCH

reasonable expenses incurred by a person in relation to the supply of human gamete, and not compensation for loss of time and earnings in particular, what is less clear is whether compensation for the loss of a donor’s time and earnings is permitted. The relevant regulatory authority should provide greater clarity on this grey area and may also wish to consider setting a limit on the amount of compensation to avoid any inducement. In the case of donors who are not employed, authorities should determine an appropriate compensatory amount, based on the time spent as a result of the procedures required to obtain the eggs for research. Authorities may need to review current legislation to determine whether legislative changes need to be enacted to implement such compensatory schemes.

8.15 In addition, the BAC, in its ‘Donation of Human Eggs for Research’ advisory report, also recommends that egg donors should be provided with prompt and full medical care when complications occur as a direct and proximate result of donating eggs specifically for research. Given that the donation of eggs for research purposes is not a commercial proposition, it is the responsibility of researchers and research institutions to provide medical care when needed. This also applies to gene editing research in embryos or germline cells. c. Proportionality

8.16 The principle of proportionality requires researchers to ensure that the risks of HNGE research are not disproportionate to the benefits, by minimising the harm to individuals and future offspring while maximising benefits gained from using gene editing. As oocyte procurement could result in potential harm to the donor (and even the risk of death), it would be important for researchers to weigh the benefits of procuring oocytes solely for gene editing research against the risks that such procurement could pose. Researchers should consider using surplus embryos created through assisted reproduction treatment for HNGE research if the risks of procuring oocytes solely for such research outweighs the benefits. Researchers may also consider alternative sources for oocytes. Issue 2: Risks involved in the use of human embryos for HNGE research

A. Risk of invalid consent and privacy breach as a result of genome sequencing 17 Genome sequencing of embryonic cells is conducted to verify whether an embryo has been edited in the desired way and to assess for off-target effects. , from blood) to act as a reference sequence. During this process, researchers may obtain genomic sequencing information from gamete donors, though it could be that not all gamete donors are adequately informed of this aspect of the research and its implications. For example, the informed consent forms used in the study on heterozygous MYBPC3 outlined above did not explicitly mention the genome sequencing aspect of the research.

Inadequate information and a poor understanding of what research participation entails, serves to undermine consent for research. This may also lead to subsequent withdrawal of consent and loss of trust if donors find out that they have not been told about genomic sequencing. Indeed, genomic sequencing could also lead to a breach of privacy and confidentiality of donors’ genomic data. For example, genomic sequencing can query nearly all the protein-coding regions of the human genome at once, including most genes believed to have roles in disease.

For researchers to find meaning in this data requires accompanying phenotypic and demographic information. This increases the likelihood that data may be linked back to the individuals from whom the data was sourced, even when de-identified, thus breaching the confidentiality of donors’ genomic data. In addition, researchers may share this data in biorepositories and databases, which may lead to misuses of genetic information that relate to risks of discrimination and social stigma.

Therefore, researchers are advised to consider the following ethical principles when using surplus embryos or oocytes procured from healthy individuals for gene editing research: a. Transparency 8.18 The principle of transparency in HNGE research emphasises openness and clarity about the research process, methods and findings, which help ensure the credibility and reproducibility of the study. It is important for researchers to ensure that donors of surplus embryos or oocytes for gene editing research are fully informed of all aspects of the research study, including any potential data that may be collected and their implications. Researchers should ensure that the information provided during the consent process is translated to the appropriate language, if needed. Thistransparency ensures valid consent and fosters trust and respect for donors’ autonomy in HNGE research.

b. Respect for persons 19 The principle of respect for persons underlies the importance of protecting research participants’ privacy and the confidentiality of information that they disclose, in order to minimise harm that they may be exposed to. Researchers and research institutions should adhere to existing guidelines and regulations, such as the Human Biomedical Research Act 2015 and the Personal Data Protection Act 2012.

Researchers should conduct genome sequencing only for legitimate scientific and medical purposes, and have a duty to ensure that only information necessary for the research is collected, avoiding unnecessary intrusion into the genetic makeup of embryo or oocyte donors. , through de-identification of research data where appropriate) and retained only for the necessary duration. They should ensure that data obtained from genome sequencing during gene editing research on human embryos is not misused, and that the privacy and confidentiality of embryo or gamete donors are not breached.

8.20 The ethical considerations surrounding oocyte procurement and the use of surplus embryos or oocytes procured for biomedical research, including HNGE research, are intricate, raising concerns related to potential harm to the donor and infringement of informed consent as well as possible breach of privacy and confidentiality of donors’ genomic data. Balancing potential scientific advancements offered by gene editing research with the ethical imperatives of informed consent and potential consequences is paramount. This can be achieved when researchers and research institutions prioritise respect for the autonomy and wellbeing of oocyte donors, as well as when they strive to ensure transparency in the research process. EQUITABLE ACCESS AND ALLOCATION OF RESOURCES

1 Technologies involving HNGE extend beyond discovering and developing therapies, particularly for rare genetic disorders, severe diseases such as cancer and treatment of infertility. This technology can also be potentially used to enhance specific traits. However, as with many new modalities in medicine, gene editing technology gives rise to concerns of inequitable access for those who are in need but cannot afford them. This affects low- and middle-income countries in particular, where there is inadequate funding and support for healthcare, and where high patient caseloads often hamper the timely delivery of treatment options to patients.

At the same time, allocation of resources to further the research and development of gene editing for clinical applications must be carefully considered, given that the technology continues to be intensely debated, particularly in regard to its ethical, legal and social implications. This chapter deliberates the potential issues arising from inequitable access and allocation of resources in the use of HNGE in research and clinical applications, as well as the ethical principles associated with the issues. Issue 1: Inaccessibility of HNGE technologies due to high costs

2 Therapies involving gene editing tools are costly due to the heavy investments by pharmaceutical companies in research and development and the market exclusivity granted by patents. 6 million) per dose. In 2022, the US Food and Drug Administration (FDA) approved Hemgenix, the first gene therapy to treat haemophilia B, a genetic disease that impairs blood clotting. 6 million) per treatment, making it the most expensive drug in the world. The high costs of cell and gene therapies can be attributed to the complexity of producing, handling and controlling the cells or viral vectors required to make them, and is far more complicated than working with the chemicals used to develop and produce traditional pharmaceutical therapies. As monogenic diseases are rare, the treatments developed are often targeted at a small pool of patients with such rare diseases, along with costs that are

set higher to maximise the return on investments for these companies. Nevertheless, it is possible that gene editing interventions may be scaled up and made accessible to more people at affordable prices in the longer term as the technology advances and becomes increasingly prevalent following the availability of generics after the expiry of patents. In addition, the Rare Disease Fund in Singapore was expanded at the end of 2023 to cover CTGTPs, which would help to mitigate the high costs faced by patients.

However, gaining equal access to HNGE technology-based gene therapy may still be a challenge for the economically disadvantaged part of the population. This, inevitably, results in health disparities due to inequalities in socioeconomic status. Therefore, researchers and research institutions should consider the following ethical principles when working on improving gene editing for use in research and clinical applications: a. Justice

3 The principle of justice encompasses the general principles of fairness and equality for all individuals, which implies that access to the benefits of biomedical research involving HNGE should be shared equitably in society. While therapeutic interventions employing gene editing may subsequently become more affordable abetted by the economies of scale of greater production, the current high cost of the technology may deny the less advantaged in society access to such medical treatments.

This would exacerbate inequity in healthcare since the benefits of gene editing technology would not be equally accessible to everyone, thereby compromising the principle of justice. , the Agency for Care Effectiveness (ACE) in Singapore), researchers, academics and the government, should consider implementing health-economic analyses and devise models of funding to ensure that HNGE technology is affordable to all individuals with a medical need.

For example, the Innovative Genomics Institute (IGI) created an expert Affordability Task Force in January 2022 to investigate the underlying drivers of high prices of CRISPR genomic therapies and to explore development of alternative pathways to manage high prices of therapies. Reforming patent protection is also important in order to balance incentivising research through robust patent protection with keeping the costs of gene editing interventions manageable.

Patent offices should also be equipped with the necessary resources and information to effectively assess the validity and effectiveness of innovations in gene editing technology proposed by manufacturers. These would help to further mitigate inequitable access and ensure that innovative gene editing treatments are truly accessible and affordable to all. b. Inclusivity

9.4 The principle ofinclusivitymaintains that benefits of research and clinical applications involving HNGE are considered a public good and should be accessible to society as a whole. If medical treatments employing gene editing are costly, individuals EQUITABLE ACCESS AND ALLOCATION OF RESOURCES with a lower socioeconomic status would not be able to access them even if they really needed them. As such, this inequity in access to medicine may be seen as differential treatment, especially if those denied access belong to minorities, which would undermine inclusivity.

In March 2023, the organising committee for the Third International Summit on Human Genome Editing argued that as interventions based on non-heritable gene editing become more widespread, a global commitment to equitable, financially sustainable and accessible treatments becomes ever more urgent and will require appropriate planning for costs and infrastructural needs for gene therapy treatments.

The European Union (EU) is currently discussing updates to its pharmaceuticals legislation, with one of its goals to create a balanced system for pharmaceuticals in the region that promotes affordability for health systems, including advanced therapy medicinal products (ATMPs), while also rewarding innovation. Issue 2: Under-representation of Asian population in clinical data involving HNGE research

5 As with most novel therapeutics, any research activity or clinical application involving HNGE would require clinical trial data for validation purposes. Participation in ongoing research or clinical trials for gene editing could allow patients to receive experimental interventions for a disease before it receives approval for human use. However, it was perceived that more clinical trials were funded and conducted in the US, Europe and the UK than in Asia. This was evident in the low participation of Asians in clinical trials according to a 2020 analysis of global participation in clinical trials conducted by the FDA.

It was reported that of 292,537 clinical trial participants globally, 76% were white, 11% were Asian, and 7% were black. As such, this may lead to insufficient representation or under-representation of Asian genomes and phenotypes where population- or ethnicity- specific insights or trends relevant to the comprehensive understanding of the gene editing intervention outcomes cannot be obtained. For example, ethnicity and pharmacogenomics are inextricably linked, and drug responses can vary based on the allele frequencies present in different ethnic populations.

Some populations may respond better to specific drugs that result in better clinical outcomes. Therefore, the design of clinical trials for HNGE research should consider the following principles: a. Justice

9.6 The principle of justice ensures fairness and equality for all individuals, whereby the benefits derived from research and clinical applications of HNGE should be equitably shared in society. Greater Asian representation in gene editing research or clinical trials will provide deeper insights and reveal trends which are specific to the Asian population that are currently lacking. If there is insufficient representation of Asians, it may not be possible to garner insights relevant to the Asian demographic needed to tailor customised healthcare for the Asia-Pacific region. This would also mean that this population may not have equal access to, or reap all the benefits from, technology or research thus undermining the principle of justice. b. Inclusivity

7 The principle of inclusivity maintains that research and applications involving HNGE should be representative of a diverse population and that the benefits of research should be shared worldwide. In order to increase the number and diversity of participants in clinical research and trials for gene editing technology, researchers, healthcare institutions and the government can strengthen recruitment and community engagement strategies to communicate the benefits of participating in biomedical research to the individual and to society. The purpose of this would be to ensure that the demographics of trial participants reflect the principle of inclusivity as well as the various genomic profiles of a multi-ethnic society like Singapore. Researchers should also improve access to information on clinical trials involving gene editing to promote the potential benefits of research.

For example, in 2019, the World Health Organization (WHO) Expert Advisory Committee on developing Global Standards for Governance and Oversight of Human Genome Editing launched the Human Genome Editing (HGE) Registry, which is a central database that collates information of clinical trials using human gene editing technology. In accordance with the principles of transparency and inclusivity, the HGE registry aims to make information on clinical trials using gene editing technology easily available to all interested stakeholders, including the public.

8 Developing new biotechnology in unchartered areas requires channelling of substantial funds and resources into the domain. Given that HNGE technology remains early stage, careful consideration should be given to the eventual delivery of resultant therapies and prudent allocation of resources, so as to ensure equitable access to healthcare, following the principles of justice and inclusivity, such that the benefits of HNGE are available to all individuals regardless of socioeconomic status.

At the same time, clinical studies of experimental treatments employing HNGE should be representative of Singapore’s diverse population, as this would enable insights into clinical outcomes relevant to the local demographic, which could be harnessed in order to uphold the principles of justice and inclusivity. Nevertheless, as clinical trials are context-specific to the type and severity of the disease, small numbers of participants may be appropriate for such clinical trials. GENETIC ENHANCEMENT AND EFFECTS ON SOCIETY

10.1 Gene editing is playing an increasing role in a variety of therapeutic applications aimed at the treatment and prevention of diseases. Advances in recent years have increased the possibilities of using gene editing for purposes that go beyond therapies and medical interventions discussed in previous chapters. We can now envisage applications of gene editing technology that include, for example, the genetic enhancement of physical attributes and cognitive abilities. This chapter discusses the ethical issues involved in applications of gene editing technology for genetic enhancement alongside the application of relevant ethical principles, namely proportionality, sustainability, respect for persons, justice, inclusivity, transparency and responsible stewardship of science.

2 Enhancing the features of the human body is by no means an unfamiliar concept. Biomedical technologies such as drugs and surgical techniques are being increasingly used to combat disease and augment the capacities of normal and healthy individuals. The best-established examples of enhancement are cosmetic surgery and doping in sports. In addition, some drugs that are used to treat narcolepsy and attention deficit hyperactivity disorder have also been shown to have small enhancing effects on attention and memory in normal individuals. There are various drugs and biomedical techniques that promise dramatic effects.

One such technique is brain-machine interfacing, which some predict may allow human brains to be connected directly to computers to improve our information processing abilities. Given their incremental use and progress in scientific technology, many forms of enhancements have found broad acceptance in society today and are recognised as improving the lives of people with disabilities. While many of the methods that are currently used for physical, functional or mental enhancements only affect the individuals and not future generations, this may not be the case if gene editing technology is used for genetic enhancements.

10.3 Genetic enhancement is the alteration of genes to improve human traits or characteristics beyond what is considered “normal” for humans. Unlike traditional medical interventions that are aimed at treating or preventing diseases, genetic enhancement focuses on enhancing abilities, characteristics or features that provide an advantage or improve quality of life. Genetic enhancement comprises both nonheritable as well as heritable genetic intervention, and can be performed for both medical or non-medical purposes. For example, non-heritable gene editing to lower the cholesterol of a healthy child of a patient with severe coronary artery disease to reduce their risk of disease to a level that is below what is average or considered

“normal” in the general population may be deemed enhancement for medical purposes, while non-heritable gene editing aimed at improving muscle strength in a normal individual may be considered enhancement for non-medical purposes. , bringing an intellectually disabled child’s cognitive ability to within normal limits) may fit best into the category of prevention and medical intervention, as they help achieve the medical goals of maintaining health and obviating a later need for treatment.

However, heritable gene editing intervention such as genetically altering an individual’s gametes to imbue their offspring with greater than average memory, intelligence and even musical talent, for example, may be considered enhancement for non-medical purposes. This chapter will only include discussions on the ethical issues arising from genetic enhancement for non-medical purposes, as it is this aspect of the technology that raises more profound ethical implications.

4 Pew Center conducted a survey between October 2019 and March 2020 in 20 countries across Europe, Russia, the Americas and the Asia-Pacific region, polling views on specific circumstances where gene editing may be used. The survey was conducted with representative samples of adults aged 18 years and older. In general, most of the countries surveyed drew distinctions when it came to specific applications of human gene editing, including showing wide support for therapeutic uses.

A demographically representative sample of 1,501 people in Singapore, which included participants of different genders, ages, education backgrounds, and regions, found that although 29% of respondents agreed that gene editing to change a baby’s genetic characteristics and boost its intelligence would be appropriate, 62% felt that such application would be a misuse of technology. While support for the notion was conceivably low, it was still substantially greater than the 14% median found in other surveyed countries.

In the same survey, 68% of respondents felt that it would be appropriate to use gene editing to change a baby’s genetic characteristics in order to treat a serious disease or conditions that the baby would have at birth, while just 22% thought such application would be considered a misuse of technology. As such, the local perspectives towards the applications of gene editing technology are largely supportive if it is used for therapeutic purposes, but not for genetic enhancement.

10.5 The primary ethical concern about permitting gene editing for the purpose of enhancement is that changes made to the genes may affect the individual as well as future generations in the case of heritable gene editing. Heritable gene editing modifies germline cells or embryos, making these changes permanent and so potentially passing them down to future generations. This raises the concern that future offsprings may be at risk from the unintended or negative consequences that might arise from genetic enhancement, potentially compromising their wellbeing, whereas the impact of non-heritable gene editing is limited to the individual undergoing the enhancement. GENETIC ENHANCEMENT AND EFFECTS ON SOCIETY

While the long-term effects of non-heritable gene editing on the individual must still be considered, the risk of affecting future generations is far lower. However, concerns about the social and psychological impacts of such enhancements remain significant for both non-heritable and heritable gene editing. Issue 1: Risks of gene editing for enhancement are disproportionate to its benefits

6 Heritable gene editing, if permitted in the future, will be employed in genetic enhancement where germline cells or human embryos are genetically modified to acquire advantageous features. Non-heritable gene editing may also be used for enhancement, namely by modifying somatic cells, where the changes would not be passed down to offspring, thus affecting only the individual undergoing the intervention. , unintended consequences) used for treatment of disease and enhancement of traits are similar, these risks may be disproportionate to the benefits offered by gene editing for enhancement purposes.

For example, despite the risks involved, applications of gene editing to treat or prevent serious genetic disorders and diseases may nevertheless be justifiable, as there is a clear medical need for this technology. However, risks involved in the applications of gene editing that go beyond addressing medical conditions per se may be less justifiable, when the goals are not directly related to improving health. Therefore, researchers, research institutions and IRBs are advised to consider one particular ethical principle in relation to applications of gene editing for enhancement if indeed they are permitted in the future: a. Proportionality

7 The principle of proportionality requires that risks of research and applications of gene editing technology are not disproportionate to its benefits by minimising the harm to individuals and future offspring while maximising its benefits. Gene editing for therapeutic purposes often targets well-understood genetic mutations, reducing the likelihood of their unintended consequences. In addition, severe illnesses caused by genetic disorders such as blood cancers and lymphomas often lack effective treatment options, yet there is gene editing that can provide a form of lifesaving therapy, albeit an alternative one.

For such applications of gene editing, the risks involved may actually be proportionate to their benefits. On the other hand, non-heritable and heritable gene editing for genetic enhancement may involve manipulating multiple genes to achieve desired traits, but the intricate interplay of genes in complex traits make it inherently challenging to accurately predict and control the outcomes. Genetic enhancement of physical or cognitive abilities, for example, are often subjective, and may be risky, especially if enhancement is not intended for medical purposes—and may be passed down to future generations in the case of heritable gene editing.

Therefore, researchers are advised to carefully weigh the benefits against the risks of applications of gene editing for enhancement should they be permitted in the future. Issue 2: Exacerbation of social inequity due to misuse of gene editing technologies for enhancement

8 Given that gene editing technologies for prevention and treatment of serious or rare diseases are currently available, it may not require significant innovation to performing intentional alterations on the human genome for enhancement of physical or intellectual traits. Heritable gene editing for the purpose of enhancement could help to select for desirable traits by correcting natural biological variants. However, it may also be misused and abused for the purpose of creating “designer babies” by removing unwanted genes. , gene doping for greater performance).

This could reinforce discrimination between genetically modified and unmodified individuals and thereby exacerbate social inequities. Nonheritable gene editing may also be employed for non-medical purposes, such as to boost memory or athletic performance, without altering the germline. However, non-heritable gene editing enhancements, despite not being passed down to future generations, could still exacerbate social inequalities by creating divisions based on access to such technology.

Additionally, the use of gene editing technology for enhancement purposes may reinforce stereotypes, prejudices and harmful practices related to persons with disabilities, thereby exacerbating discrimination against certain marginalised groups, such as persons with disabilities. This may create demand for programs designed to produce “more desirable” and “better” kinds of human beings—an approach that borders on eugenics. Therefore, researchers and research institutions are advised to consider several ethical principles, outlined below, when considering applications of gene editing for enhancement if these are permitted in the future:

a. Justice 9 The principle of justice encompasses the general principles of fairness and equality for all individuals. It implies that access to the benefits of research and clinical applications involving gene editing technology should be equitably shared in society. In reality, however, the high costs of gene editing would mean that only a small group of wealthy individuals may gain access to the technology for the purpose of enhancement, which could then skew the distribution of perceived advantages and disadvantages of genetic enhancement among people.

As a result, the selected or desirable traits would become the exclusive domain of a privileged, wealthy group, and could subject future generations to discrimination thus exacerbating and reinforcing existing social division and inequality. Protecting the interests of future generations is important, particularly those who are vulnerable to discrimination or social inequities, GENETIC ENHANCEMENT AND EFFECTS ON SOCIETY

such as individuals with disabilities or those from lower-income backgrounds. This must be considered as the collective and shared responsibility of both the research community and the wider public. If permitted, the current generation’s decisions to use gene editing technologies to enhance the traits of their children-to-be could affect subsequent offspring. Given that applications of gene editing technology for enhancement could exacerbate social inequity, it may be necessary to limit their uses to cases where they do not result in unfair advantage or disadvantage for certain individuals.

Other uses of gene editing technology, such as editing genes to enhance physical traits or cognitive abilities that could create unequal opportunities in sports, education, or employment, may need to be limited, as they could worsen existing social inequalities. Researchers, scientists and society as a whole should also develop a strong sense of stewardship of environmental, biological and social factors to ensure the wellbeing and interests of future generations are not compromised if such applications of gene editing technology are permitted in the future. b. Inclusivity

10 The principle of inclusivity maintains that benefits of research and clinical applications involving gene editing technology are considered a public good and should be accessible to everyone within society. Gene editing technology for genetic enhancement, if permitted in the future, can promote inclusivity by providing individuals with the opportunity to enhance traits such as intelligence or physical strength, thereby narrowing disparities that arise from natural genetic variations. This could lead to a more inclusive society where everyone has access to the means to improve themselves, regardless of their initial genetic makeup.

However, potential applications of gene editing technology for genetic enhancement could also create disparities among those who cannot afford or are unable to access such enhancements. Therefore, it would be prudent to ensure equitable access to this technology for genetic enhancement, to prevent widening existing inequalities. Gene editing for enhancement may reduce the number of disabled individuals and, consequently, able-bodied individuals may develop less empathy and sensitivity towards persons with disabilities.

Hence, inclusive policymaking is important and requires researchers, scientists and the government to engage with the views and shared experiences of people living with the conditions that are targeted for intervention. Their perspectives are essential in shaping policies that reflect the needs and concerns of affected communities. If the use of gene editing technology for genetic enhancement is permitted in the future, research and governance frameworks should be established by research institutions and relevant regulatory authorities to ensure that such technology is accessible to the public.

Researchers and scientists should ensure that the benefits of applications of gene editing technology for genetic enhancement are made available to everyone, to prevent any further widening of social disparities. 11 In view of the potential discrimination that may arise from the use of gene editing technology for enhancement, regulatory authorities and IRBs should conduct more studies to assess the societal impact of permitting genetic enhancement, in terms of whether it will increase the vulnerability of particular populations to risks of harm and discrimination, and create frameworks and regulations to prevent discrimination. In addition, they should also create policies to ensure equitable access to gene editing technology, which reduce potential disparities in the access and use.

Initiatives or programmes to foster inclusion and support for those who are vulnerable to discrimination should be developed and implemented. Social inclusion can also be promoted by eliminating discriminatory practices, educating the public and implementing inclusive workplace policies that provide equal opportunities. These policies may include guidelines for improving communication with people with disabilities by taking into consideration their disabilities, providing assistive devices and allowing them to feel a sense of belonging at the workplace.

Social inclusion objectives such as improving the ability, opportunity and dignity of the disadvantaged on the basis of their identity should also be put in place, so as to foster an inclusive environment. c. Transparency

10.12 The principle of transparency requires researchers and their institutions to report and disseminate research methods, analysis and data openly, clearly, comprehensively and in a timely manner to ensure that results are reproducible and reliable, and to facilitate proper interpretation and dissemination of findings by other researchers. Given that researchers in studies that misuse gene editing technology for enhancement may not disclose their methods, analysis and data as accurately and openly as the researchers in permitted research would, it is important for researchers, research institutions and approving authorities to ensure that reporting mechanisms are in place to prevent misuse or abuse of the technology. Issue 3: Shift in attitudes and behaviours towards reproductive choices

13 Heritable gene editing for enhancement purposes could lead to undesirable societal expectations and alter the perception of conventional reproductive choices among future generations. This is because reproductive technology offers a more certain way to select the characteristics of the next generation than does choice of reproductive partners. For example, one study on Down’s syndrome screening in England and Wales concluded that although the frequency of births of people with Down’s syndrome had not changed much over the study period, the availability of prenatal screening and termination has had a significant impact on the number of children who would have otherwise been born with the conditions for which screening is available. , children with no genetic diseases or conditions), and terminating pregnancies that are diagnosed as having severe genetic conditions. ).

If gene editing technology was to become more common and widely utilised, this could bring into question the choices of people who refuse to use such technology. A shift in behaviours and expectations may affect the evaluation of the responsibilities of prospective parents towards their future children. This could, in turn, place pressure on prospective parents to have children using gene editing technology to secure commonly accepted GENETIC ENHANCEMENT AND EFFECTS ON SOCIETY

conventional outcomes, resulting in less tolerance for natural human flaws and weaknesses. Furthermore, some are concerned that parents who genetically enhance their children could burden them with unrealistic expectations. The choice of “desirable traits” that do not have a medical basis could be quite subjective. Therefore, researchers and research institutions are advised to consider the following ethical principles when considering applications of gene editing for enhancement if permitted in the future: a. Sustainability

10.14 The principle of sustainability provides that research and clinical applications involving gene editing technology should ensure that adverse effects or harm rendered by the use of such technology are not perpetuated to future generations. The use of gene editing technology for enhancement could lead to the future generation facing psychological distress to conform to society’s perception of ‘normal’ reproductive choices, and could compromise the welfare of future offspring. Hence, such applications of gene editing technology may not be sustainable. b. Responsible stewardship of science

10.15 The principle of responsible stewardship of science emphasises the moral requirement of researchers to consider the ethical guidelines governing applications of heritable gene editing in the pursuit of biomedical research. Outcomes of biomedical research involving gene editing technology should always be aligned with society’s values and perceptions in order to ensure responsible stewardship of science. However, since heritable gene editing for the purpose of enhancement may result in a shift in social norms and behaviours towards reproductive choices, any research or clinical trials involving the use of gene editing technology for enhancement may not be in alignment with society’s values and perceptions, as they may lead to undesirable expectations that could harm society. c. Respect for persons

16 The principle of respect for persons refers to the autonomy of individuals making decisions related to biomedical research involving gene editing or its clinical applications. The autonomy of a person may be compromised if they are not fully informed of the possible benefits, risks and repercussions arising from research and clinical applications of gene editing technology. In the context of heritable genetic enhancement (if permitted in the future), parents make decisions on behalf of their unborn children.

While this may be consistent with the responsibility of parents to act in the best interests of their offspring, some may consider it important to ensure that such decisions respect the autonomy of the child-to-be. Hence, researchers and research institutions should be mindful of the ethical considerations to ensure that parents responsibly safeguard the best interests of their children and respect their autonomy when they are mature and intelligent enough to make their own decisions, and ensure that the life opportunities of the enhanced children are not constrained.

10.17 Applications of gene editing technology for both non-heritable and heritable genetic enhancement have potential benefits in terms of enhancing cognitive, physical and functional abilities. However, such applications of gene editing technology raise many ethical implications and profound questions of fairness, societal norms and unintended consequences, which will require careful consideration. Therefore, applications of gene editing technology for genetic enhancement should only be considered after thorough public consultation and social debate, as well as once the safety and efficacy of such applications become well-established. GOVERNANCE AND FRAMEWORK TOOLS FOR HNGE

1 New and emerging technologies in biomedicine, such as HNGE, hold great potential in improving human health. Gene editing tools such as CRISPR-Cas9 may be used to correct aberrant genes and modify sequences within the human genome to treat genetic diseases, improve fertility and enhance desirable traits. However, HNGE technology is currently still in its infancy, with many efficacy and safety concerns yet to be addressed.

Teething issues with the technology include off-target effects, unintended genetic changes and genetic mosaicism, that could be passed down to future generations in cases such as heritable gene editing for treatment of diseases or infertility. High costs of existing therapy regimens involving HNGE may also limit the technology to just an elite group of privileged people, and in doing so, exacerbate social inequality. In the event that gene editing for enhancing specific traits is allowed, the move would also be detrimental to human population diversity, if genes for the same desirable traits are selectively altered.

2 As with other technological advances, gene editing raises ethical and social issues that must be addressed by having proper governance frameworks put in place. In 2021, the WHO published a governance framework for HNGE derived from good practices on the governance of emerging technologies. The recommended framework identifies values and principles that justify the need for governance measures, and how the review or strengthening of such measures may be carried out.

It also sets out an assessment of the tools, institutions, processes and considerations necessary for the successful implementation of oversight and governance measures for HNGE. Proper governance is not limited to legislative frameworks and regulations, but also includes other norms that may influence the development of the technology at various levels. We elaborate here on the governance and framework tools for HNGE that should be put in place at the following respective levels:

a. Institutional research level: Institutional policies and Institutional Review Boards (IRBs)

11.3 Policies and practices put in place for HNGE research warrant regular reviews by institutions to manage the risks and maximise the potential benefits emanating from such research. Notably, the review should take into consideration the views of the public, patients, or others with a vested interest in the activities conducted by such institutions. For instance, a study carried out in Japan found that stakeholder involvement in the governance of emerging medical technologies—for example, through collaboration between the scientific research community and other parties (e.g., government bodies, experts and the general public) within society—was critical to establishing an effective regulatory system. This is because perceptions about the use of HNGE may vary from one individual to another and the interests of a representative public should be examined in policy-making.

11.4 Institutions should ensure that all staff involved in HNGE research share responsibility and accountability for the institution’s research being conducted according to appropriate regulatory, ethical and scientific standards within the levels of acceptable institutional risk. For example, institutions in Singapore conducting any gene editing research on germline cells or oocytes that falls within the scope of ‘restricted research’ under the Human Biomedical Research (Restricted Research) Regulations 2017, should adhere to the requirements of the Human Biomedical Research Act 2015, and seek the necessary approval from the Ministry of Health prior to conducting the research.

11.5 In Singapore, IRB review is required when a research study is conducted at institutions or partner institutions under the IRB’s purview (e.g., hospitals and polyclinics). IRB review is also required if the research involves human subjects and/or patients from that IRB or healthcare cluster , or is conducted by, or under the direction of, an employee under the purview of the IRB or healthcare cluster. IRBs should ensure that the research is conducted in accordance with high ethical standards, adheres to regulatory frameworks, and that appropriate measures are taken to protect the rights and welfare of human participants in HNGE research. b. Clinical level: Regulatory bodies, government and funding agencies, and standard operating procedures (SOPs)

11.6 Regulatory bodies, government organisations and funding agencies that are developing internal standard operating procedures (SOPs) for research and/or clinical trials of HNGE, should implement guidelines and put in place robust systems, to understand, monitor and minimise or mitigate the relevant risks and their impact GOVERNANCE AND FRAMEWORK TOOLS FOR HNGE on research subjects and patients undergoing clinical trials. This may be achieved by considering the anticipated limitations of the proposed technology and via a comparison with available standards for safety and efficacy studies. One example would be the “Cellular & Gene Therapy Guidances” published by US FDA for industry, FDA reviewers and FDA staff. c. National level: Legislation and regulatory guidance

11.7 Governments and policy makers should ensure that laws and guidelines pertaining to the application and research involving HNGE are reviewed and revised regularly. National policies should be developed after careful analysis of the latest scientific evidence, and be in alignment with prevailing societal values. Such reviews may be conducted by advisory committees convened to examine safety concerns, sound practices and the scope of allowable activities, in order to make informed recommendations for decision making. Stakeholder consultations with the scientific community, patient advocates, and the general public should be carried out with feedback sought, to ensure that policies properly take into consideration the varied interests of all stakeholders in society.

, laws and regulations, codes of ethics or research review processes) are framed and in terms of allocating responsibilities for biosafety and research ethics. The study also found that there was a lack of clarity on the scope of the governance measures, such as the differentiation between non-heritable gene editing and heritable gene editing, as well as between research and treatment. Public consultations would be desirable in order to address the inadequacy of available information, short timelines for responses and the lack of public awareness about the consultation processes.

The study also discovered a lack of information about enforcement or organisations that actively monitor for non-compliance, which may suggest that while governance measures do in theory exist, the reality may be entirely different. II. Tools and Approaches to Strengthen Existing Research Governance

11.9 There is a wide variety of strategies that could be introduced to fortify existing research governance frameworks, such as self-regulation by professional bodies, development of guidelines, ethics and training courses, strengthened institutional practices, the introduction of HNGE registries and implementation of whistle-blowing mechanisms. Each of these strategies is explored in detail below. a. Professional self-regulation

11.10 Professional self-regulation within the scientific community can be an effective way to hold scientists conducting HNGE research accountable to their peers and society, thereby serving as an important deterrent to misconduct in this arena. Professional self-regulation may rely on ethical codes developed by advisory committees and could include representatives from patient groups, public interest groups, advocacy organisations and other parts of society. Professional societies can also help develop guidelines for the sector, setting out best practices, standards and ethical considerations in HNGE research. Well-crafted guidelines would have the flexibility to be reviewed regularly in response to the rapidly evolving field of gene editing technology, in contrast to legislative reform.

11.11 However, professional self-regulation may give rise to potential conflicts of interest as the party laying out guidelines or best practices may have certain self-interests in pursuing the research or treatment. In addition, there might not be sufficiently rigorous action taken against those who violate established standards because of professional solidarity or other secondary interests, such as financial gain. For instance, conflicts of interests in research or clinical practice may arise due to financial relationships between researchers or medical professionals and entities such as biopharmaceutical or biotechnology companies. b. Providing education and training specific to HNGE for researchers and clinicians

11.12 Additional educational training or ethics modules specific to HNGE may be developed for graduates who are looking to pursue research in gene editing or professions that may involve clinical applications of gene editing. These modules could cover topics on research integrity, ethics and the latest scientific developments in HNGE, as well as various national policies and guidelines relevant to the field. Providing training through public education, engagement, empowerment of individual rights and media communication will facilitate better understanding and communication between researchers and the public. This would, in turn, enable the scientific community to better understand public concerns and needs, thereby ensuring that information is conveyed accurately and thus preventing any distortion of public perceptions and expectations relating to HNGE.

11.13 Institutions can fund or support educational or training programmes for their staff and IRB members, so as to equip them with knowledge of gene editing technology, developments in HNGE research, appropriate ethical standards, national guidance documents and advisories, as well as legislative updates. c. Reinforcement of institutional practices

11.14 Institutions may review existing IRB ethics review processes and develop SOPs for HNGE research. Institutions should also ensure that these SOPs are revised regularly GOVERNANCE AND FRAMEWORK TOOLS FOR HNGE and updated to keep pace with the changes and developments in HNGE research, technologies and legislation.

11.15 In addition, institutions may put in place annual reporting requirements, declaration mechanisms and processes for self-monitoring of HNGE research.These mechanisms may also be used to monitor achievements and other outcomes achieved in ongoing gene editing research, including any advances in knowledge, as well as to report on any adverse events arising from clinical trials.

11.16 Institutions may also review existing training programmes for IRBs to ensure members are kept abreast of the latest trends and developments in HNGE, and remain informed and competent in order to be able to review HNGE research applications. Institutions can also encourage greater discussion amongst staff and researchers about ongoing HNGE research protocols and their safeguards, in order to enhance understanding of how HNGE research should be conducted to appropriate ethical standards. d. Setting up HNGE registries

17 National registries tracking germline gene editing research on embryos and nonheritable gene editing clinical trials can be set up to monitor all research and clinical trials involving human gene editing. Such registries help enable information about HNGE research and clinical trials to be made easily accessible to relevant stakeholders. For instance, the WHO has set up a Human Genome Editing (HGE) Registry, which is a global centralised database that collates information pertaining to clinical trials for human gene editing technology. , patients). Failure to register any research that falls within the scope of the HGE Registry may prevent appropriate oversight and valuable feedback from stakeholders, which may amount to a violation of the principle of responsible stewardship of science, transparency, and inclusivity.

18 In the wake of the CRISPR baby scandal, there is an urgent need to better regulate HNGE research, and to ensure that any ongoing and subsequent germline gene editing research activities are on a safe and sensible path. Proposals for all ethicallyapproved basic research studies that employ gene editing tools in human embryos and gametes, including those for evaluating treatment efficacy and safety, could be placed in an open registry.

Setting up a registry for germline gene editing research could encourage legitimate submissions for fundamental and pre-clinical research and avert abuse by businesses seeking to commercialise gene editing technologies prematurely. Such registries could also enable early recognition of any research that risks overstepping pre-defined boundaries, by allowing researchers or interested stakeholders to flag up potentially dangerous germline gene editing research.

The set up of such registries for germline gene editing research should involve a collaborative effort among scientific institutions, governmental bodies, regulatory agencies and ethicists.

11.19 For clinical trials involving non-heritable gene editing, well-established registries can provide valuable information on the safety of treatments and the therapeutic efficacy of non-heritable gene editing. This is applicable to HNGE where long-term monitoring may be necessary to assess the safety and efficacy of the technology. Non-heritable gene editing clinical trial registries could help prevent selective publication and reporting of research outcomes, reduce unnecessary duplication of research effort and allow patients and the wider public access to the available clinical trials that are planned or ongoing, to facilitate decisions on participation. These registries could also provide an overview of the landscape and data of existing research to ethics review boards that might be considering approval of new research studies of similar work or scope.

11.20 Data may not always be made publicly available for treatments employing nonheritable gene editing technology carried out under the hospital exemption rule (i.e., innovation salvage therapy cases) but which fall outside the scope of clinical trials. Setting up open-access registries of such treatments could help widen access to treatment strategies and data, provide evidence of the efficacy of treatments and also help identify treatment-related costs that may be considered for reimbursement. e. Whistleblowing mechanisms

11.21 In addition to a registry to collect clinical trial data involving gene editing applications, the WHO has also recommended the introduction of whistleblowing mechanisms at an institutional or national level. This is to establish effective reporting channels and to help maintain comprehensive protection and support for those who report illegal, unregistered, unethical or unsafe HNGE research.

11.22 Research institutions can provide a well-advertised, safe, and confidential internal mechanism for reporting allegations. To enable and encourage researchers or the public to report concerns about unethical HNGE research from outside an institution, a new reporting mechanism can be set up in the form of a confidential portal, website or hotline, which would allow individuals to file a report at any time and from any location. Follow-up procedures should be put in place to review any reports filed GOVERNANCE AND FRAMEWORK TOOLS FOR HNGE

and to demonstrate that action has been taken where appropriate. A two-stage investigative process can be implemented, beginning with a preliminary enquiry to verify that the reported concern is valid and not frivolous, followed by a more detailed, rigorous investigation if warranted. It would be important to establish the foregoing investigative and sanctioning functions via government legislation, in consultation with the relevant research institutions or funding agencies, and with clear levers to address misconduct.

11.23 Protective mechanisms should be set up to mitigate potential harm that may result to individuals (e.g., researchers or members of the public) for reporting on unethical HNGE research. Individuals who do bring such incidents to light should have their identities kept confidential and be provided with appropriate guidance and professional advice throughout the reporting process. f. International mechanism for reporting unethical germline gene editing experiments

11.24 In 2006, the WHO’s Expert Advisory Committee on Developing Global Standards for Governance and Oversight of Human Genome Editing established an International Clinical Trials Registry Platform (ICTRP) for clinical trials involving gene editing, through a World Health Assembly resolution. While the ICTRP system can be leveraged to report unethical experiments, establishing a system supported by WHO sends a signal to the world that reporting of unethical experiments is the responsibility of researchers globally. III. Governance Framework for Heritable Gene Editing and Gene Editing in Embryos or Germline Cells for Research Purposes

25 Heritable gene editing requires proper governance frameworks, since any genetic modifications made may be passed down to successive generations. In particular, heritable gene editing for clinical research and clinical applications are deemed to pose greater risks to future progeny, due to the deleterious long-term health effects stemming from the manipulation of germline cells or embryos. Furthermore, the clinical use of heritable gene editing may heighten social tensions such as inequity and undesirable social expectations.

In comparison, the risks associated with gene editing in embryos or germline cells for basic research purposes are lower, as research conducted on germ line cells in vitro do not affect future generations. Therefore, the extent of oversight in developing governance and framework tools should be commensurate with the extent of corresponding risk and sensitivity, whether for clinical research and clinical applications of heritable gene editing, or for the basic research activities of gene editing in embryos or germline cells.

11.26 Due to the ethical issues involved in HNGE, as well as the potential for misuse and downstream implications for patients, and potentially, their progeny, robust and comprehensive governance frameworks will be critical in ensuring the safety and welfare of patients undergoing such treatments or clinical trials. Institutions, professional bodies and governments should collaborate to develop policies, guidelines and regulatory frameworks that accord with prevailing societal values, minimising risks and maximising potential healthcare benefits to the public.

12.1 Applications of gene editing in human biomedical research have helped to advance developments in genetics, disease modelling and therapeutics. The increasing use of gene editing in clinical applications offers promise for treating genetic disorders, infertility, enhancing personalised medicine and improving health outcomes. While the technology has the potential to confer resistance to diseases and enhancement of traits in the future, they may also bring about unintended consequences and expose individuals and future generations to unknown long-term effects. Hence, it would be imperative that these issues be reviewed holistically and to develop appropriate recommendations to guide researchers, healthcare professionals and IRBs on the ethical use of gene editing to ensure patient safety and welfare.

2 The BAC has conducted a comprehensive review of the ethical, legal and social issues arising from gene editing in human biomedical research and clinical applications. From its review, it has issued recommendations to guide the responsible use of such technology. These recommendations consider the ethical implications that may arise from such use, and the potential benefits and risks to individuals and future generations.

The objectives of the BAC’s recommendations include not only encouraging greater ethical debates around genetic enhancements and discourse to address emerging ethical concerns involved in HNGE, but to also encourage and enable researchers to conduct HNGE research in an ethical manner. This could also potentially lead to safer and more effective medical treatments for various genetic disorders. The BAC’s recommendations on HNGE will help shape policies that balance scientific progress with ethical considerations and thereby facilitate decision making.

12.3 In its advisory report, the BAC recommends that researchers, research institutions, IRBs, and healthcare professionals consider the five substantive principles, namely (i) respect for persons; (ii) solidarity; (iii) justice; (iv) proportionality; and (v) sustainability, as well as the three governance principles of (i) inclusivity; (ii) transparency; and (iii) responsible stewardship of science for HNGE research and clinical applications. The BAC’s recommendations for the safe and ethical use of gene editing technology are summarised as follows (refer to Chapters 6, 7, 8, 9 and 10 for a detailed discussion of these recommendations): a. Non-heritable gene editing (for research and clinical applications)

12.4 For any research on, and clinical application of, non-heritable gene editing, the BAC recommends that researchers, research institutions and clinicians should ensure a favourable risk-benefit ratio for patients undergoing clinical trials or clinical interventions involving non-heritable gene editing. Patients must be informed of the potential risks and possible complications, and informed consent and IRB approval should be obtained from patients prior to their procedure.

CONCLUSION 5 Given that the long-term safety and efficacy of non-heritable gene editing are not fully established, the BAC recommends that researchers, research institutions and clinicians should conduct long-term follow-up on patients in clinical trials involving non-heritable gene editing in order to mitigate the risk of any adverse development arising from the treatment manifesting itself only later.

It would also be important for researchers and research institutions to take appropriate measures, such as establishing guidelines on the duration of follow-ups and monitoring the frequency of follow-ups when developing guidelines for evaluating and managing off-target effects. The guidelines should also include other aspects and risks of the treatment, such as the specificity of the gene editing tool, the types of tissues affected, unintended genetic changes and the potential for immune responses.

Researchers and research institutions should also develop comprehensive frameworks for risk assessments, which involve creating standardised protocols for identifying, evaluating and managing risks, in order to ensure consistent implementation across different studies. These would help to anticipate and manage uncertainties and longterm consequences associated with non-heritable gene editing.

12.6 Furthermore, the BAC recommends communication strategies for reporting outcomes and educating patients about the potential risks and benefits of nonheritable gene editing. Clear and consistent communication can help patients make informed decisions and remain vigilant for any potential delayed effects. Additionally, researchers should refer to the BAC’s advisory report on the ‘Ethical Use of Big Data and Artificial Intelligence (AI) in Biomedical Research’, which provides guidance to decision-makers who work with big data and AI in health and research, and recommends good practices for the safeguarding of data and collaborative data sharing practices. b. Gene editing on germline cells or embryos for research

7 The BAC does not recommend culturing human embryos whose genes have been edited beyond 14 days, maintaining that the creation of human embryos solely for research purposes can only be justified when there is strong scientific merit in, and potential benefit from, such research. It is conceivable that the BAC may reconsider its position at some point in the future should stronger evidence come to light of scientific merit in culturing human embryos whose genes have been edited after 14 days, subject to public consultations and engaging with stakeholders.

Furthermore, the BAC currently recommends that women donating surplus embryos or undergoing oocyte procurement for any approved gene editing research should be fully informed of all aspects of the research study by researchers and research institutions. This includes the risks involved, any potential data that may be collected, and the implications thereof. Donors should also be afforded sufficient time to give their consent prior to undergoing the procedures.

The BAC also recommends that researchers and research institutions take responsibility to ensure that data obtained from genome sequencing during gene editing research on human embryos are not misused and to safeguard the security of data storage. 12.8 With regard to compensation of women undergoing oocyte procurement for gene editing research, the BAC recommends that the relevant regulatory authority clarify its stance on whether compensation for loss of time and earnings should be allowed, given that Singapore’s Human Cloning and Other Prohibited Services Act 2004 allows only for reimbursement of reasonable expenses incurred by a person in relation to the supply of human gamete. The BAC also recommends that the relevant regulatory authority consider capping compensation to avoid inducements.

c. Heritable gene editing for clinical research and clinical applications

12.9 Clinical research and clinical applications of heritable gene editing for (i) treatment of diseases; (ii) infertility; (iii) conferring resistance to diseases; and (iv) enhancement of traits, have raised ethical and safety concerns including unintended consequences, long-term effects and other issues around consent, autonomy and inequality. The BAC does not recommend clinical research and clinical applications of heritable gene editing for any purpose in the near future, as there is insufficient evidence from current research to give confidence that such applications of HNGE technology are irrefutably safe and ethical. Hence, more research would need to be conducted to determine whether clinical research and clinical applications of heritable gene editing are genuinely safe and ethical before they can be recommended in the future.

10 Nonetheless, if and when the risks involved (including those of exacerbating genetic discrimination and social inequalities) in the applications of gene editing technology are sufficiently mitigated in the future, the BAC may then reconsider whether heritable gene editing may be recommended for use as experimental intervention in certain situations to prevent catastrophic conditions, or to combat diseases for which there are no other treatment options available. Such situations may potentially benefit the future child where the benefits involved may outweigh the risks.

The experimental intervention involving heritable gene editing must be conducted as a clinical trial with the appropriate approvals from ethics and regulatory bodies. , input from experts in genetics, bioethics, law, and various stakeholders such as policymakers, and the public) for such experimental intervention would be important, to provide an additional layer of oversight. This would enable a comprehensive evaluation from a broader perspective, embracing potential societal impacts and international implications.

12.11 The governance of research and clinical applications of gene editing technology is important and serves to uphold ethical principles, foster responsible innovation and promote ethical advancement of such technology. The BAC’s recommendations, which are aimed at governing the ethical and responsible use of gene editing technology are summarised as follows (refer to Chapter 11 on ‘Governance and Framework Tools for HNGE’ for a detailed discussion):

a. The BAC recommends that research institutions regularly review policies and practices in place to manage risks and maximise potential benefits that may arise from HNGE research. The BAC also recommends that IRBs should ensure that HNGE research is conducted in accordance with high ethical standards, adheres to regulatory frameworks and that appropriate measures are taken to protect the rights and welfare of human participants in HNGE research. b. The BAC recommends that regulatory bodies, government and funding agencies encourage the implementation of guidelines and put in place robust systems to understand, monitor, and minimise or mitigate the risks and their impact on research subjects and patients undergoing HNGE clinical trials. This is carried CONCLUSION

out by also giving due consideration to the anticipated limitations of gene editing technology and comparison with available standards for safety and efficacy studies.

c. The BAC recommends that governments and policy makers should regularly review and revise legislation and guidelines pertaining to applications and research involving HNGE. National policies should be developed after careful review of scientific evidence and in alignment with societal values. The BAC also recommends stakeholder consultations to be conducted with the scientific community and patient advocates, to obtain feedback from the general public, so as to ensure that policies pertaining to HNGE are well aligned with societal values. d.

The BAC recommends various approaches and tools be introduced to enhance existing research governance frameworks for HNGE, such as self-regulation by professional bodies, development of guidelines, ethics and training courses, reinforcement of institutional practices, establishment of HNGE registries and implementation of a whistle-blowing mechanism.

e. With regard to heritable gene editing for clinical applications, the BAC recommends that the extent of oversight in developing governance and framework tools should be commensurate with the extent of risks and sensitivity involved in clinical applications of heritable gene editing. Given that clinical applications of heritable gene editing for (i) conferring resistance to diseases and (ii) enhancement of traits pose more significant ethical concerns, as compared to clinical applications of heritable gene editing for treatment of diseases or infertility, the BAC recommends that clinical applications of heritable gene editing to confer resistance to diseases and to enhance traits be subject to more stringent governance.

12.12 In addition to the BAC’s recommendations on the governance of research and clinical applications of HNGE as summarised above, it would also be important to maintain flexibility in the governance of HNGE, given that gene editing technology is a rapidly evolving field. This flexibility would allow scientific advancements to be adapted to reflect ethical considerations and thereby help foster a responsiveness to emerging ethical challenges, while also ensuring responsible and ethical use of constantly evolving gene editing technology. Achieving a balance between flexibility and ethical oversight is crucial for navigating the complex landscape of research and clinical applications of gene editing technology. In short, the governance of research and clinical applications of gene editing technology should be guided by the following considerations:

a. Guidance from international organisations 12.13 International organisations such as WHO develop guidelines and recommendations on a regular basis (e.g., WHO’s framework for governance of human genome editing ). It would be important to consider international organisations’ guidance on gene editing, and ensure a consistent ethical framework and standards are adopted across borders, which would help promote global collaboration. This would also avert disparities in regulatory approaches, fostering a unified stance on responsible gene editing. As the field of gene editing is continuously evolving, the BAC’s recommendations should remain aligned with the latest international guidelines and recommendations, and fine-tuned to fit the local context.

b. International governance and collaborations 14 International governance and collaborations on HNGE are important, as they encourage research and clinical applications of gene editing to adhere to universally accepted principles. Such collaborations can also promote responsible development through joint research and sharing of best practices, while also promoting international ethical standards in gene editing.

It would also be important for policymakers and organisations developing recommendations and guidelines pertaining to gene editing technology, to collaborate with international institutions and bodies that have an interest in the field of gene editing, such as WHO, International Bioethics Committee (IBC) of the United Nations Educational, Scientific and Cultural Organization (UNESCO), and American Society of Human Genetics, to discuss and share ethical issues arising from such technology.

Sharing of information on laws and legislations relevant to gene editing, as well as engaging in collaborative international governance and oversight of gene editing, will enable better alignment of ethical standards. c. Continuous stakeholders and public engagement

12.15 Stakeholders and public engagement are, and should continue to play, an important part in research and clinical applications of gene editing technology and its advancement. Such engagement is crucial for ethical and transparent decisionmaking, helping ensure diverse perspectives are considered and that policies are shaped to align with broader societal values. Through continuous engagement of the relevant stakeholders and the public, the feedback obtained will allow policy makers, researchers and healthcare professionals to understand the public’s concerns and ensure that HNGE progresses in a way that best serves the public’s interests. d. Public education to raise awareness of the benefits and risks of HNGE applications

16 Public education plays a vital role in raising the public’s awareness of the benefits, risks and ethical issues involved in research and clinical applications of gene editing technology while also enhancing the public’s knowledge of the latest developments in gene editing. Public education also provides opportunities for the public to reflect and have discussions on developments pertaining to gene editing technology. Education also enables the public to make informed decisions about supporting or participating in gene editing research or clinical trials that involve gene editing technology.

In addition, public education clarifies any misperceptions regarding gene editing and equips individuals to whom this knowledge has been imparted, to differentiate between legitimate scientific advancements and potential misconceptions or fraudulent activities. This, in turn, reduces the risk that individuals unwittingly participate in unethical or questionable gene editing technology clinical trials. CONCLUSION

17 In conclusion, the ethical landscape surrounding gene editing requires that academics, researchers, healthcare professionals, IRBs and research and healthcare institutions consider the ethical principles highlighted in this report when using gene editing technology for research or clinical applications. With further advancements in this field, it would be imperative that the potential benefits of technology are balanced against their associated risks, as well as their ethical and societal implications. Public education and continuous stakeholder engagement are pivotal in fostering a responsible and ethical approach to gene editing.

Striking this balance will not only guide the scientific community, but will also encourage the broader public to remain informed and be actively involved in shaping the ethical framework that governs the responsible use of gene editing technology. This chapter summarises the key ethical principles that are applicable to HNGE in biomedical research and clinical applications. It also sets out recommendations for clinicians, researchers, research institutions, regulatory authorities and IRBs in the process and evaluation of HNGE applications.

As the HNGE technology is constantly evolving, this report will be reviewed periodically to ensure that the BAC recommendations are kept up to date. I. Ethical Principles Applicable to the Use of HNGE in Biomedical Research and Clinical Applications 13.1 The principle of respect for persons underlies the need for informed consent of individuals participating in biomedical research involving gene editing or its clinical applications, to protect their autonomy and rights. This would enable individuals to decide whether to undergo non-heritable gene editing and engage in germline human gene editing for their offspring, if and when the safety, efficacy and long-term effects are well-established and if and when gene editing is approved for use.

13.2 The principle of solidarity reflects the importance of general altruism and other prosocial motives as a basis for participation in biomedical research. For instance, research in human gene editing may reap benefits for society by enabling faster and more accurate diagnosis of diseases or conditions in patients, introducing more targeted treatments, and allowing early prevention of the occurrence of genetic disorders. Yet at the same time, the misuse and abuse of the technology for inappropriate purposes or the enhancement of personal trait preferences could lead to the neglect or failure to discharge obligations towards certain subgroups, such as those afflicted by a rare disease.

13.3 The principle ofjusticeholds that gene editing technology and therapy be accessible to the public according to a plausible theory of justice. However, the technology involved may raise concerns about ensuring fair access to therapy due to the high cost. As such, treatments involving the use of gene editing technology may not be widely and readily accessible to the entire population, particularly the lower socioeconomic strata, which may lead to societal inequity issues.

13.4 The principle of proportionality requires that the regulation of research should be proportional to the degree of possible threats to autonomy, individual welfare or the public good. As such, any interference with individuals’ decisions and/or actions,

RECOMMENDATIONS FOR CLINICIANS, RESEARCHERS, RESEARCH INSTITUTIONS, RECOMMENDATIONS FOR CLINICIANS, RESEARCHERS, RESEARCH INSTITUTIONS, REGULATORY AUTHORITIES, AND INSTITUTIONAL REVIEW BOARDS (IRBs)

should not exceed what is sufficient to achieve necessary regulation to promote public interest. The principle also implies that the risk in any acceptable programme of research, and the stringency of its regulation, should not be disproportionate to any anticipated benefits. When assessing the use of gene editing technology in biomedical research or clinical purposes, the potential benefits to individuals and society brought about by the editing of the human genome should outweigh the anticipated risks emanating from such research and clinical applications. The stringency of any regulation or governance framework developed for research employing gene editing, including a de facto prohibition of specific research activities, must be proportionate to the risks being mitigated.

13.5 The principle of sustainability maintains that research processes and outcomes should not unfairly jeopardise or prejudice the welfare of future generations. In the context of human gene editing in biomedical research or clinical purposes, while gene editing technology can bring about social benefits, research involving human embryos and heritable gene editing for treatment of diseases, conferring resistance, enhancement of traits, or treatment for infertility, might harm the offspring and their future generations directly or indirectly due to the risks of genetic mutation. Researchers and research institutions are encouraged to allocate and expend research resources appropriately to support HNGE research activities, as long as the resources are not misused and their research is aligned with the United Nations (UN) Sustainable Development Goals.

II. Governance Principles Applicable to the Use of HNGE in Biomedical Research and Clinical Applications 13.6 The principle of inclusivity stipulates that the benefits of HNGE research and potential clinical applications are considered a public good, and as such, should be accessible to everyone. However, the ethical implications of HNGE could exacerbate already divergent views of technology in society. Hence, there is a need to carefully consider the knowledge and perspectives of HNGE that are informed by different social, cultural and religious beliefs, and to work closely with different groups of people to facilitate ‘community-engaged research’, where a wide range of opinions and perspectives are considered in the conceptualisation of research plans.

13.7 The principle of transparency relates closely to ethical responsibility and moral and legal liability for the decisions and actions arising directly from research studies which should be attributed to researchers and their institutions. Research methods, analysis and sampled data must be reported and disseminated openly, clearly, comprehensively and in a timely manner to ensure that results are reproducible and reliable, and to facilitate proper interpretation and dissemination of findings by other researchers. Transparent reporting mechanisms may also be devised to investigate concerns about possible unlawful doings, as well as to provide support and protection for whistle-blowers.

13.8 According to the principle of responsible stewardship of science, the processes and outcomes of HNGE research should be aligned with the values, needs, and expectations of society, which can be identified through stakeholder engagement. This principle extends beyond the dissemination of information and demands that the views of all stakeholders be considered, as elaborated in the principle of inclusivity.

9 The BAC recommends that research and research institutions should put in place an oversight mechanism for any research involving HNGE, to ensure that research activities are conducted appropriately. For instance, an oversight committee could be established within research institutions to oversee the research priority setting process for gene editing research. , research, medical, administrative) to advise on current policy and research considerations, assist with the identification of stakeholders and provide inputs into finalising the research priorities.

It is important for researchers and institutions to exercise caution in view of the uncertainty and long-term risks associated with gene editing technology in both research and clinical applications. It is also important to put in place clear and well-established protocols and processes for oversight and review, to ensure that research is conducted in an ethical manner.

13.10 Researchers and research institutions should set research priorities based on societal needs while formulating strategies to prevent or mitigate the occurrence of existing errors arising from HNGE. This would ensure that social and scientific benefits are maximised, and that potential risks are minimised. In addition, established ethical practices, ethical guidelines and legislation should be adhered to by researchers when conducting research on humans, with particular attention given to issues of integrity and conflicts of interest.

13.11 Clinicians should consider current established methods of intervention to treat or prevent diseases in individuals and future offspring until the safety and efficacy of HNGE technology are demonstrated. For while HNGE may be used for a variety of indications and in investigative studies of diseases (e.g., enhancement of specific traits, therapeutic interventions, determining genetic targets for diagnostic purposes as well as in the treatment of fertility), many research groups’ findings are largely preliminary and require further studies to determine the long-term safety and efficacy of gene editing technology. IV. Recommendations for Non-Heritable Gene Editing (for Research and Clinical Applications)

13.12 For any research and clinical applications involving non-heritable gene editing, researchers, research institutions and clinicians should ensure a favourable riskbenefit ratio for patients undergoing such clinical trials or clinical interventions.

13.13 Governments, regulatory bodies and IRBs should establish an evaluation framework at the institutional level, comprising guidelines and oversight committees, to assess the benefits of gene editing technology vis-à-vis the risks such as off-target effects, the types of tissues affected, unintended genetic changes and the potential for immune responses.

13.14 Researchers, research institutions and clinicians should ensure that patients undergoing gene editing interventions or HNGE clinical trials have an appropriate understanding of the intervention and are made fully aware of the potential risks and complications prior to receiving the treatment. They should also ensure that patients’ informed consent and IRB approval are obtained prior to the procedure. RECOMMENDATIONS FOR CLINICIANS, RESEARCHERS, RESEARCH INSTITUTIONS, REGULATORY AUTHORITIES, AND INSTITUTIONAL REVIEW BOARDS (IRBs)

15 Regulatory bodies should establish guidelines on the required information that should be covered in informed consent for researchers and research institutions to refer to, in order to ensure that all relevant information on the gene editing intervention is made known to the patient or participant. Due to the complexity of gene editing technology, researchers and clinicians should ensure that patients are sufficiently informed and understand the potential benefits and risks involved.

Researchers and clinicians should also obtain patient consent and ensure their safety by continually engaging patients with follow-ups and further discussions, should new information relating to the intervention arise. Given that the off-target effects could be sensitively and comprehensively quantified, researchers, research institutions and clinicians should inform patients of the potential off-target risks, including their likelihood and severity during genetic consultations, in accordance with the principle of respect for persons.

13.16 For clinical applications of non-heritable gene editing involving patients with diminished or no capacity (e.g., minors), clinicians must obtain valid informed consent from their persons (e.g., parents or next of kin), in accordance with the SMC Ethical Code and Ethical Guidelines and the Mental Capacity Act 2008. For non-heritable gene editing research, again involving patients with diminished or no capacity, researchers are required to obtain valid informed consent from their legally authorised persons in accordance with the Human Biomedical Research Act 2015.

13.17 Researchers and clinicians who are involved in research and clinical applications involving HNGE technology should be properly trained to assess the potential benefits and risks of gene editing interventions accurately, and to be able to conduct the necessary counselling and informed consent for patients. This may include training in the fields of genetics, genomics and gene editing technology along with ethics, law and sociology. Institutional oversight should also be established for continuous training of researchers and clinicians involved in HNGE technology.

13.18 Researchers, principal investigators of HNGE clinical trials, as well as clinicians providing treatment involving non-heritable gene editing should take responsibility to ensure that clinical trials of non-heritable gene editing or therapies are designed to minimise any unprecedented harmful effects to patients in accordance with the principle of proportionality. Appropriate measures, such as establishing guidelines for evaluating off-target effects and risk-benefit assessments, should be adopted by researchers to anticipate and/or manage uncertainties and long-term consequences associated with non-heritable gene editing to uphold responsible stewardship of science.

13.19 Researchers, research institutions and clinicians should ensure that the risks of any unintended consequences arising from non-heritable gene editing interventions becoming heritable are avoided as much as possible, and that these risks are documented and assessed appropriately.

13.20 Research institutions should implement robust quality management systems and standard operating procedures, while also ensuring that good manufacturing practices are adhered to, in order to achieve consistency, safety and ethical compliance in the HNGE research conducted.

13.21 Researchers, research institutions, and clinicians should continuously review whether existing regulations and guidelines are adequate for managing the risks and benefits of HNGE. 13.22 Researchers and physicians should conduct long-term follow-ups on patients and participants in clinical trials, evaluating new therapeutic modalities for non-heritable gene editing, to help mitigate the risk of any delayed adverse event arising from the treatment. This is particularly important, as the long-term safety of non-heritable gene editing has not been fully established.

13.23 Public agencies (e.g., the Agency for Care Effectiveness (ACE) in Singapore), researchers, academics, and the government, should consider implementing healtheconomic analyses and models of funding, to ensure that HNGE technology is affordable to all individuals with a medical need.

13.24 Researchers, healthcare institutions and the government should strengthen recruitment and community engagement strategies to communicate the individual and societal benefits of participating in biomedical research. These initiatives would help increase the number, and widen the spectrum, of participants in clinical research and trials involving gene editing technology, thereby allowing the diverse genomic profiles of a multi-ethnic society in Singapore to be appropriately represented.

13.25 Given that the clinical development of non-heritable gene editing remains at an early stage, researchers and research institutions should accord careful consideration to the eventual delivery of resultant therapies and prudent allocation of resources, taking into account the principles of justice and inclusivity. This is to ensure equitable access to healthcare across the population and also help ensure that benefits reaped from HNGE could be made available to all individuals regardless of socioeconomic status.

13.26 Researchers and research institutions should ensure that clinical studies of experimental treatments employing HNGE technology for non-heritable gene editing are representative of Singapore’s diverse population. This would yield valuable insights into clinical outcomes relevant to the local demographic to be harnessed for use, while also upholding the principles of justice and inclusivity. V. Recommendations for Gene Editing on Germline Cells or Embryos for Basic Research

27 The BAC does not recommend culturing human embryos whose genes have been edited beyond 14 days, and that the creation of human embryos solely for research purposes can only be justified when there is strong scientific merit and potential benefit from such research. Singapore’s Human Biomedical Research (Restricted Research) Regulations 2017 prohibits research involving human embryos that are more than 14 days old from the time of creation, excluding any period when the development of the embryos was suspended.

The regulations also only allow surplus embryos created in assisted reproduction treatment to be used for biomedical research following IRB approval. This effectively prohibits the creation of embryos for research purposes, even when there is strong scientific merit and potential benefit to be had. In light of this, regulatory authorities should review current regulations pertaining to restricted research in order to enable further advancements in biomedical research, including gene editing research. RECOMMENDATIONS FOR CLINICIANS, RESEARCHERS, RESEARCH INSTITUTIONS, REGULATORY AUTHORITIES, AND INSTITUTIONAL REVIEW BOARDS (IRBs)

13.28 Researchers and research institutions should ensure that consent for donation of surplus oocytes or embryos is kept separate from the consent for treatment of women undergoing fertility treatment. Researchers and institutions should ensure that the researcher seeking consent for the donation of eggs and embryos for research is not the physician administering the fertility treatment.

13.29 Research institutions should establish an independent panel to interview women who intend to donate eggs specifically for research (i.e., those who are not undergoing fertility treatment), given that the process of donating eggs for research is timeconsuming, invasive and associated with a certain degree of discomfort and risk. The panel must be satisfied that the women are of sound mind, understand the nature and consequences of their donation and have given explicit consent of their own free will, without any inducement, coercion or undue influence.

13.30 Researchers should ensure that women are fully informed of the risks involved and given sufficient time to express consent prior to undergoing oocyte procurement procedures for gene editing research, thus safeguarding their autonomy. Researchers and research institutions should also implement safeguards to protect oocyte donors and ensure that there is no coercion or undue influence on their decision to donate.

13.31 The relevant regulatory authority should consider setting a limit on the amount of compensation under Section 13 of Singapore’s Human Cloning and Other Prohibited Practices Act, to avoid any inducement. In the case of donors who are not employed, the regulatory authority should determine an appropriate compensatory amount for these donors based on their time spent undergoing the procedures required to obtain the eggs for research. The regulatory authority should also review current legislation to determine whether legislative amendments are required to implement proposed compensation.

13.32 Researchers should weigh the benefits of procuring oocytes solely for gene editing research against the risks that such procurement could pose, as oocyte procurement could result in potential harm to the donor including the risk of death. Researchers should only consider using surplus embryos created through assisted reproduction treatment for HNGE research if the risks of procuring oocytes solely for such research outweighs the benefits, so as to ensure proportionality. Researchers may also consider alternative sources for oocytes.

13.33 In upholding respect for persons, researchers and research institutions should take responsibility to ensure that data obtained from genome sequencing during gene editing research on human embryos are not misused and safeguard the security of data storage, so that the privacy and confidentiality of embryo or gamete donors are not breached. Researchers and research institutions should adhere to existing guidelines and regulations, such as the Human Biomedical Research Act 2015 and the Personal Data Protection Act 2012. VI. Recommendations for Heritable Gene Editing for Clinical Research and Clinical Applications

13.34 The BAC, presently, does not recommend heritable gene editing for clinical research and applications until such time that the safety and efficacy of such technology can be validated and as the long-term outcomes are as yet unknown. Therefore, researchers and clinicians must validate the safety, including the long-term safety, and efficacy of gene editing technology before it can be used for clinical research and applications involving heritable gene editing.

13.35 Heritable gene editing for clinical research and clinical applications should not be conducted until they are proven to be safe and beneficial to the research participants and society as a whole, since heritable gene editing could result in unintended off-target mutations, chromosomal mosaicism and other unforeseen adverse consequences, which could expose research participants and people undergoing such procedures to potential harm, affecting future generations.

13.36 Researchers and research institutions should conduct more research to develop ways of mitigating off-target effects and other unintended mutations from heritable gene editing on human embryos, so long as the safety of gene editing-established pregnancy is yet to be established. Further in vitro research on embryos or gamete precursors is also required to fully understand the implications of heritable gene editing technology.

13.37 If heritable gene editing for clinical research is deemed safe enough and permitted in the future, researchers and research institutions should conduct intergenerational monitoring which could help determine the long-term side effects of heritable gene editing on the individual that may be passed on to future generations and assess its safety and efficacy for clinical use. VII. Recommendations for Non-Heritable and Heritable Gene Editing for Genetic Enhancement (if and when permitted)

13.38 If genetic enhancement is permitted in the future, researchers should weigh the benefits of applications of gene editing for the enhancement of physical attributes or cognitive abilities against their risks. This is because such applications are often subjective and may be risky, especially if the enhancement is for non-medical reasons and may be passed down to future generations, in the case of heritable gene editing.

39 Researchers and clinicians should review the need to limit the applications of gene editing technology for enhancement to cases where it does not lead to either an unfair advantage or disadvantage for certain individuals, as genetic enhancement for other uses could exacerbate social inequity. The BAC does not recommend other uses of gene editing technology, such as editing genes to enhance physical traits or cognitive abilities with the sole intention to create unequal opportunities in sports, education or employment, as this could perpetuate existing social inequalities.

Governments, funding agencies and IRBs should consider implementing oversight measures to ensure that the use of gene editing technology adheres to the principle of justice. These could include developing regulatory frameworks to control the application of gene editing to prevent misuse for non-therapeutic enhancements that favour certain groups.

13.40 Researchers, scientists, and society as a whole should foster a strong sense of stewardship of environmental, biological and social factors to protect the wellbeing and interests of future generations if such applications of gene editing technology are permitted in the future. RECOMMENDATIONS FOR CLINICIANS, RESEARCHERS, RESEARCH INSTITUTIONS, REGULATORY AUTHORITIES, AND INSTITUTIONAL REVIEW BOARDS (IRBs)

13.41 If the use of gene editing technology for genetic enhancement is indeed permitted in the future, research institutions and relevant regulatory authorities should establish research and governance frameworks to ensure such technology is accessible to the public. Scientists, clinicians, institutions and regulatory authorities should also ensure that the benefits of applications of gene editing technology for genetic enhancement are made available to everyone, thereby averting any further widening of social disparity. Researchers, scientists and the government should engage with the views and shared experiences of people living with conditions that are targeted for HNGE intervention, and ensure that their perspectives are considered in shaping policies that reflect the needs and concerns of affected communities.

13.42 Given that individuals who are not genetically enhanced (if permitted in the future) or have disabilities may face exclusion or bias in education or employment settings, regulatory authorities and IRBs should conduct further studies to assess the societal impact of permitting genetic enhancement in terms of increasing the vulnerability of particular populations to risks of harm and discrimination, and create frameworks and regulations to prevent discrimination. In addition, they should create policies to ensure equitable access to gene editing technology in order to reduce potential disparities in access and use.

13.43 Scientists, research institutions, clinicians, medical institutions and approving authorities must ensure that reporting mechanisms are in place to prevent misuse or abuse of gene editing technology for enhancement. This is in consideration that researchers may not disclose their research methods, analyses, and data for research studies that misuse gene editing technologies for enhancement as accurately and openly as compared to when researchers conduct gene editing research that is permitted.

13.44 The BAC does not recommend applications of gene editing technology for enhancement that could lead to future generations facing psychological distress to conform to society’s perception of ‘normal’ reproductive choices, which could compromise the future offspring’s welfare.

13.45 Researchers and research institutions should ensure that the outcomes of biomedical research involving gene editing technology are always aligned with society’s values and perceptions to ensure responsible stewardship of science. 13.46 Researchers and research institutions should take ethical considerations into account to ensure that parents responsibly safeguard the best interests of their children and respect their autonomy when they have sufficient maturity and intelligence to make their own decisions, and ensure that the life opportunities of genetically enhanced children are not constrained in the context of heritable genetic enhancement (if permitted in the future). VIII. Recommendations for the Governance of Research and Clinical Applications Involving HNGE a. Institutional research level: Institutional policies and Institutional Review Boards (IRBs)

13.47 Research institutions should regularly review institutional policies and practices to manage risks and maximise potential benefits that may arise from HNGE research and consider the views of the public, patients or others with a vested interest in the activities conducted by such institutions. Institutions should also ensure that all staff involved in HNGE research share responsibility and accountability for the institution’s research being conducted according to appropriate regulatory, ethical and scientific standards within the levels of acceptable institutional risk. IRBs should also ensure that the research is conducted in observance of high ethical standards, adheres to regulatory frameworks and that appropriate measures are taken to protect the rights and welfare of human participants in HNGE research.

b. Clinical level: Regulatory bodies, government and funding agencies, and standard operating procedures (SOPs) 13.48 Regulatory bodies, government organisations and funding agencies that are developing internal standard operating procedures (SOPs) for HNGE research or clinical trials should be encouraged to implement guidelines and establish robust systems to help understand, monitor, and minimise or mitigate the relevant risks and their impact on research subjects and patients undergoing clinical trials. This should allow for the anticipated limitations of the proposed technology in comparison to available standards for safety and efficacy studies.

c. National level: Legislation and regulatory guidance 13.49 Governments and policy makers should constantly review and update legislation and guidelines pertaining to the application and research involving HNGE. National policies should be built upon careful review of the latest scientific evidence and be in alignment with prevailing societal values. Such reviews may be conducted by advisory committees convened to examine safety concerns, sound practices and the scope of allowable activities, in order to issue policy recommendations.

13.50 Stakeholder consultations with the scientific community, patient advocates and indeed the wider public should be conducted to solicit opinion that would help ensure that policy decisions reflect the varied interests of differing stakeholders in society. IX. Tools and Approaches to Strengthen Existing Research Governance a. Professional self-regulation

13.51 There should be professional self-regulation within the scientific community so that scientists conducting HNGE research are responsible and accountable to their peers as well as to society as a whole. They should adhere to ethical codes developed by advisory committees or guidelines developed by professional societies, and set out best practices, standards, and ethical considerations in HNGE research. b. Providing education and training specific to HNGE for researchers and clinicians

13.52 Academic, research and healthcare institutions should develop educational training or ethics modules specific to HNGE for graduates who are looking to pursue research in gene editing or professions engaged in clinical applications of HNGE. These would cover topics such as research integrity, ethics, the latest scientific developments in HNGE as well as the relevant national policies and guidelines. Institutions are RECOMMENDATIONS FOR CLINICIANS, RESEARCHERS, RESEARCH INSTITUTIONS, REGULATORY AUTHORITIES, AND INSTITUTIONAL REVIEW BOARDS (IRBs) also recommended to fund or support educational or training programmes for their staff and IRB members, to equip them with knowledge of gene editing technology, developments in HNGE research, appropriate ethical standards, national guidance documents and advisories, as well as legislative reform in this area.

c. Reinforcement of institutional practices 13.53 Research and healthcare institutions should continually assess existing IRB ethics review processes and develop SOPs for HNGE research. These should be revised regularly and incorporate the latest developments in HNGE research, technology and legislation. Research and healthcare institutions may also implement annual reporting requirements, declaration mechanisms and processes for self-monitoring of HNGE to track achievements and outcomes, as well as to report any adverse events arising from clinical trials. The BAC also recommends that institutions review existing training for IRBs to ensure members are kept abreast of the latest trends and developments in HNGE, and so remain informed and competent in terms of their ability to review HNGE research applications.

d. Setting up HNGE registries 13.54 The BAC recommends for establishing national registries to track and monitor research and clinical trials involving HNGE, such as germline gene editing research on embryos and non-heritable gene editing clinical trials, to allow easy access of HNGE research and clinical trials information to relevant stakeholders. e. Whistleblowing mechanisms

55 Research institutions or governments could introduce whistleblowing mechanisms at institutional or national levels, respectively, in order to establish effective reporting channels and provide comprehensive protection and support to those who report illegal, unregistered, unethical or unsafe HNGE research. Research institutions are recommended to set up a reporting mechanism via a confidential portal, website or hotline, that would allow individuals to report at any time and from anywhere.

Governments and regulatory bodies should also put in place follow-up procedures to investigate any information disclosed and demonstrate that action has been taken where appropriate. It would also be important for governments and regulatory bodies to establish the foregoing investigative and sanctioning functions through national legislation, in consultation with the relevant research institutions or funding agencies, with clear levers to address misconduct.

13.56 Research institutions should set up protective mechanisms to mitigate potential harm to the individuals who report unethical HNGE research. Their identities should be protected and they should be provided appropriate guidance and professional advice throughout the reporting process. X. Governance Framework for Heritable Gene Editing and Gene Editing in Embryos or Germline Cells for Research Purposes

13.57 Research institutions and regulatory authorities should ensure that the extent of oversight in developing governance and framework tools is commensurate with the extent of ethical, social and health risks involved, whether for clinical research and clinical applications of heritable gene editing, or basic research activities of gene editing in embryos or germline cells. This is in consideration of the greater risks that heritable gene editing poses to future progeny, such as potential deleterious longterm health effects which may exacerbate social inequity. GLOSSARY Alzheimer’s disease – A degenerative brain disorder that is common in the elderly, characterised by progressive deterioration of mental functions, leading to impaired cognition and increased reliance on others for daily activities.

Amniocentesis – A procedure in which a small amount of the amniotic fluid surrounding the foetus is withdrawn for testing for chromosomes and genetic disease. Autologous (of cells or tissues) – Obtained from an individual’s own tissues, cells or DNA. Azoospermia– A medical condition where there is no measurable sperm in a man’s ejaculate (semen). Common causes include blockage or decreased sperm production by the testis.

Carrier – Someone who carries only one copy of a mutant gene in question. A carrier usually shows no symptoms or very mild symptoms for the disease gene that he or she carries, as two copies of the disease gene are required for a full-blown manifestation of the disease. A carrier has the risk of transmitting the mutant gene to the next generation. Chromosome – A threadlike structure of nucleic acids and proteins found in the nucleus of most living cells, carrying genetic information in the form of genes.

Clinical Ethics Committees (CECs) – Hospitals are required under Singapore’s Healthcare Services Act (HCSA) to set up CECs to advise clinicians on clinical ethical issues and also review other specific ethical issues relating to care and management of patients in the healthcare institutions. While CECs primarily play an advisory role, they also assume an adjudicatory role in specific instances where the prescribed medical treatment involves complex ethical dilemmas. Chorionic Villus Sampling (CVS) – A prenatal test that involves taking a sample of tissue from the placenta to test for chromosomal abnormalities and other genetic problems.

Cystic fibrosis – Cystic fibrosis (CF) is an inherited disorder that causes severe damage to the lungs, digestive system and other organs in the body. It affects the cells that produce mucus, sweat and digestive juices. These secreted fluids are normally thin and slippery. But in people with CF, a defective gene causes the secretions to become sticky and thick. Instead of acting as lubricants, the secretions plug up tubes, ducts and passageways, especially in the lungs and pancreas.

DNA – Deoxyribonucleic acid (DNA) is the molecule that carries genetic information for the development and functioning of an organism. Each DNA is a linear molecule made up of nucleotides or bases. There are four different types of bases in DNA and the order in which these bases are arranged determines the protein to be formed. Each individual’s body contains an identical set of DNA in nearly all of its cells. A great fraction of cellular DNA is located in the cell nucleus (where it is called nuclear DNA), while the remaining can be found in the mitochondria (where it is called mitochondrial DNA).

DNA methylation – An epigenetic mechanism that occurs by the addition of a methyl group to DNA; this regulates gene expression by changing the activity of a DNA segment. Epigenetics – The study of heritable changes in gene expression that are caused by factors such as DNA methylation without a change in the DNA sequence itself. Embryo – The initial stage of development of a multicellular organism. At eight weeks of gestation, the embryo becomes known as a foetus. Extra-chromosomal DNA (ecDNA) – Refers to any DNA that is found off chromosomes, either inside or outside of the nucleus of a cell.

Foetal blood sampling (FBS) – A procedure to draw foetal blood from the umbilical cord of the foetus during pregnancy. Frameshift mutation – An insertion or deletion involving a number of base pairs that is not a multiple of three. As the formation of proteins involves reading the RNA sequence in multiples of three, this disrupts the reading frame and causes premature termination of translation. Gamete – Sperm or egg cell. Gene – A gene is the basic physical and functional unit of heredity. It is made up of DNA which carries instructions to make molecules of RNA and proteins.

Gene therapy – Treatment of a genetic disorder by inserting functional genes to replace, supplement or manipulate the expression of nonfunctional or abnormal genes. Genetic variant – An alteration in the most common DNA nucleotide sequence. Genome – The complete set of DNA (genetic material) in an organism. The genome contains the master blueprint for all cellular structures and activities for the lifetime of the cell or organism. Found in every nucleus of a person’s many trillions of cells, the human genome consists of tightly coiled threads of DNA and associated protein molecules, organised into structures called chromosomes.

Genotype – A specific set of alleles (variant forms of a gene) at particular position on the chromosome. Germ cell (Germline) – The cell (or cell line) from which sperm and egg (gametes) are derived. Human immunodeficiency virus (HIV) – A virus that attacks the body’s immune system. If HIV is not treated, it can lead to AIDS (acquired immunodeficiency syndrome), a condition in which there is progressive failure of the immune system. Induced haematopoietic stem cells (iHSCs) – An adult somatic cell, such as a human skin cell, that has been reprogrammed (or induced) into self-renewing stem cells capable of replenishing all blood lineages.

Induced pluripotent stem cells (iPSCs) – An adult somatic cell, such as a human skin cell, that has been reprogrammed (or induced) into an embryonic pluripotent state. GLOSSARY Institutional Review Board (IRB) – A committee that reviews for a proposed research study to ensure adherence to relevant ethical, legal and institutional standards. Such boards are designated to approve (or reject), monitor and review biomedical and behavioural research involving humans. For biomedical research, IRB approval is required by law before any subjects can be recruited.

Intrauterine insemination – A procedure for treating infertility where sperm is placed directly into the uterus using a small catheter. In vitro fertilisation (IVF) – A clinical and laboratory procedure whereby the eggs and sperm from a couple are extracted and fertilised outside their bodies. Such a procedure is a type of assisted reproduction aimed at increasing the chances of a couple conceiving a baby. Low-frequency mutation – Somatic mutation with allele frequency lower than 1% in an individual’s DNA.

Meiotic arrest – During the formation of oocytes in females, meiosis (cell division of germ cells that produces the gametes) arrests twice. The first arrest occurs during prophase 1 in embryogenesis and lasts until puberty. The second meiotic arrest occurs after ovulation during metaphase 2. microRNA (miRNAs) – A class of non-coding RNAs that play important roles in regulating gene expression. Monogenic diseases – Diseases caused by variation in a single gene and are typically recognised by their striking familial inheritance patterns. Examples include sickle cell anaemia, cystic fibrosis, Huntington disease and Duchenne muscular dystrophy.

Muscular dystrophy – Caused by changes (mutations) in the genes responsible for the structure and functioning of a person’s muscles. These mutations cause changes in the muscle fibers that interfere with the muscles’ ability to function. Overtime, this causes increasing disability.

Mutation – A gene mutation is a permanent change in the DNA sequence that makes up a gene. It ranges in size from one DNA base to a large segment of a chromosome. Gene mutations can be inherited from a parent or acquired during a person’s lifetime. If a mutation occurs in an egg or sperm cell during a person’s life, there is a chance that the person’s children will inherit the mutation. Most mutations do not cause genetic disorders. For example, some mutations alter a gene’s DNA base sequence but do not change the function of the protein made by the gene.

Missense mutations – Missense mutations occur when a single nucleotide base in a DNA sequence is swapped for another one, resulting in a different amino acid being encoded at a particular position in the resulting protein. Mosaicism – A condition in which cells within the same person have a different genetic makeup. Off-target edits – Non-specific and unintended genetic modifications that occur at untargeted sites in the genome that are genetically similar to the target site. Oncogenesis – The process through which healthy cells become transformed into cancer cells. Oocyte – An egg cell.

Percutaneous umbilical blood sampling (PUBS) – A test that takes foetal blood directly from the umbilical cord. Phenotype – The observable characteristics of the expression of a gene. Pleiotropic – The phenomenon in which a single gene affects two or more apparently unrelated phenotypic traits, resulting in multiple phenotypic expressions. Polygenic disease – Disease caused by the joint contribution of a number of independently acting or interacting genes. Examples include hypertension, coronary heart disease and diabetes.

Preimplantation genetic testing for aneuploidies (PGT-A) – A technique used to analyse the number of chromosomes present in IVF embryos. Preimplantation genetic testing for chromosomal structural rearrangements (PGT-SR) – A test performed on embryo biopsies to screen embryos for chromosomal imbalances (extra or missing chromosome material) resulting from a parental structural rearrangement. Preimplantation genetic testing for monogenic gene defects (PGT-M) – A treatment which involves checking the genes or chromosomes of embryos for a specific genetic condition. Prenatal – During pregnancy and before birth.

Primitive streak – A transient structure whose formation, on day 15 of human development, marks the start of gastrulation which is the early developmental process in which an embryo transforms from a one-dimensional layer of epithelial cells (blastula) and reorganises into a multi-layered and multi-dimensional structure called the gastrula. Protein – Large and complex molecules of amino acid residues that play many critical roles in the body. They do most of the work in cells and are required for the structure, function and regulation of the body’s tissues and organs.

Retinitis pigmentosa (RP) – A group of rare eye diseases that affect the retina (the lightsensitive layer of tissue in the back of the eye). RP makes cells in the retina break down slowly over time, causing vision loss. RNA – RNA, or ribonucleic acid, is a nucleic acid present in all living cells. Its principal role is to act as a messenger carrying instructions from DNA for controlling the synthesis of proteins. Severe Combined Immunodeficiency (SCID) syndrome – A group of rare disorders caused by mutations in different genes involved in the development and function of infectionfighting immune cells.

Sickle-cell anaemia – One of a group of inherited disorders known as sickle cell disease. It affects the shape of red blood cells, which carry oxygen to all parts of the body. GLOSSARY Single nucleotide polymorphism (SNP) – A genomic variant at a single base position in the DNA. Somatic cell – All the body cells except the reproductive (germ) cells. Somatic or adult stem cells – An unspecialised cell, present in a tissue or organ, that is able to replicate itself and develop into specialised cell types of that tissue or organ, or into some other cell types.

Spinal muscular atrophy (SMA) – A genetic disorder where cells of the spinal cord die, resulting in progressively weaker muscles. Spinocerebellar ataxia – A group of inherited brain disorders. It affects the cerebellum, a part of the brain vital to coordination of physical movement, and sometimes the spinal cord. This inherited condition worsens over time and causes specific problems with coordination with, usually affecting eyes, hands, legs and mobility, and speech.

Stem cell – An unspecialised cell that is able to replicate itself and develop into specialised cell types (such as a red blood cell, nerve, or heart cell). Stem cells divide to form daughter cells, in which some daughter cells differentiate into specialised cell types, and some daughter cells retain the stem cell property to divide and make more new stem cells. Spermatogonial stem cells (SSC) – Adult stem cells in the testis which continuously generate daughter cells that differentiate into sperm cells. They keep their cellular pool constant through self-renewal.

Thalassaemia – An inherited blood disorder caused when the body does not make enough of a protein called haemoglobin, an important part of red blood cells.