第二屆人類基因組編輯國際峰會組委會聲明
翻譯 | 葉水送 邸利會
2015年12月，美國國家科學(xué)院和美國國家醫(yī)學(xué)院、英國皇家學(xué)會和中國科學(xué)院在華盛頓特區(qū)舉辦了一次國際峰會，討論與人類基因組編輯相關(guān)的科學(xué)、倫理和監(jiān)管問題。最后，峰會組委會發(fā)布了一份聲明，確定了可在當(dāng)前監(jiān)管和治理協(xié)議范圍內(nèi)，可以進行的研究和臨床應(yīng)用。那時，該委員會還表示，進行任何可遺傳的生殖細(xì)胞編輯臨床使用是不負(fù)責(zé)任的。此外，它呼吁繼續(xù)就這一快速發(fā)展的技術(shù)的潛在收益、風(fēng)險和監(jiān)督進行國際討論。
作為致力于促進人類基因組編輯的深入和國際討論的一部分，香港科學(xué)院、英國皇家學(xué)會、美國國家科學(xué)院和美國國家醫(yī)學(xué)院組織了第二次香港人類基因組編輯國際峰會，評估不斷發(fā)展的科學(xué)圖景、可能的臨床應(yīng)用，以及隨之而來的對人類基因組編輯的社會反應(yīng)。雖然我們，第二次峰會的組委會，對體細(xì)胞基因編輯在臨床試驗中的迅速發(fā)展表示贊賞，但我們?nèi)匀徽J(rèn)為，進行任何生殖細(xì)胞編輯的臨床使用仍然是不負(fù)責(zé)任的。
人類基因組編輯研究
基礎(chǔ)和臨床前研究正在迅速推進體細(xì)胞和生殖細(xì)胞基因組編輯科學(xué)的發(fā)展。更好地理解和設(shè)計基因組編輯技術(shù)，包括堿基編輯技術(shù)，已經(jīng)顯著提高了效率和精確度，同時大大減少了脫靶事件的發(fā)生。正如預(yù)期的那樣，現(xiàn)在，對患者體細(xì)胞基因組編輯正在測試之中。
改變胚胎或配子的DNA可以讓攜帶致病突變的父母擁有健康的遺傳上相連的孩子。然而，胚胎或配子的可遺傳基因組編輯帶來的風(fēng)險仍然難以評估。人們擔(dān)心基因編輯只發(fā)生在早期胚胎的某些細(xì)胞中，同時有未經(jīng)編輯的細(xì)胞，這樣會長期導(dǎo)致疾病。生殖細(xì)胞編輯不僅會對個體產(chǎn)生意想不到的有害影響，也會對個體的后代產(chǎn)生意想不到的有害影響。對特定性狀的改變可能對其他性狀產(chǎn)生意想不到的影響，這些性狀可能因人而異并且響應(yīng)環(huán)境影響。
遺傳變化產(chǎn)生的影響的多樣性使得難以對利益和風(fēng)險進行全面評估。然而，如果這些風(fēng)險得到解決并且符合許多其他標(biāo)準(zhǔn)，生殖細(xì)胞基因組編輯在未來可能會被接受。這些標(biāo)準(zhǔn)包括嚴(yán)格的獨立監(jiān)督、迫切的醫(yī)療需求、缺乏合理的替代方案，長期隨訪計劃以及對社會影響的關(guān)注。即便如此，公眾的可接受程度可能因司法管轄區(qū)而異，導(dǎo)致不同的政策反應(yīng)。
組委會得出結(jié)論，臨床實踐的科學(xué)理解和技術(shù)要求仍然很不確定，且風(fēng)險太大，無法在此時允許進行生殖細(xì)胞編輯的臨床試驗。然而，過去三年的進展以及本次峰會的討論表明，現(xiàn)在是時候為這些試驗確定嚴(yán)格、負(fù)責(zé)任的轉(zhuǎn)化途徑。
建議的轉(zhuǎn)化途徑
生殖細(xì)胞編輯的轉(zhuǎn)化途徑需要遵循廣泛接受的臨床研究標(biāo)準(zhǔn)，包括過去三年發(fā)表的基因組編輯指導(dǎo)文件中闡明的標(biāo)準(zhǔn)。[1] 這樣的途徑將需要建立臨床前證據(jù)和基因修改的準(zhǔn)確性的標(biāo)準(zhǔn)，臨床試驗從業(yè)者的能力評估，專業(yè)行為的可執(zhí)行的標(biāo)準(zhǔn)，以及與患者和患者倡導(dǎo)團體的強有力的伙伴關(guān)系。
生殖細(xì)胞編輯的臨床應(yīng)用報告
在這次峰會上，我們聽到一個意外且令人深感不安的說法，即人類胚胎已經(jīng)過編輯和植入，導(dǎo)致一例懷孕和一對雙胞胎的誕生。我們建議進行獨立評估以驗證此事，并確定所聲稱的DNA修飾是否已發(fā)生。即使基因修改得到驗證，該試驗也是不負(fù)責(zé)任的，不符合國際規(guī)范，其缺陷包括醫(yī)學(xué)適應(yīng)癥不足，研究方案設(shè)計不合理，未能達到保護研究對象福利的倫理標(biāo)準(zhǔn)，且在臨床試驗的制定、審查和實施中缺乏透明度。
持續(xù)舉行的國際論壇
組委會呼吁持續(xù)組織國際論壇，以促進廣泛的公眾對話，制定戰(zhàn)略增加公平獲取以滿足沒有得到足夠服務(wù)的人口的需求，加快監(jiān)管科學(xué)的發(fā)展，提供有關(guān)治理方案信息的交流平臺，促進制定共同的監(jiān)管標(biāo)準(zhǔn)，并通過計劃中的和正在進行的實驗的國際登記加強研究和臨床應(yīng)用的協(xié)調(diào)。
除了建立國際論壇外，組委會還呼吁世界各國的學(xué)術(shù)界和科學(xué)、醫(yī)學(xué)的學(xué)習(xí)社區(qū)繼續(xù)舉辦國際峰會，審查基因組編輯的臨床應(yīng)用，收集不同的觀點，提供不同的觀點，將決策者的決定告知（公眾），制定建議和指導(dǎo)方針，以及促進國家間、司法管轄區(qū)之間的協(xié)調(diào)。
參考資料
[1] See, for example, National Academies of Sciences, Engineering, and Medicine, Human Genome Editing: Science, Ethics, and Governance (Washington, DC: The National Academies Press, 2017) and Nuffield Council on Bioethics, Genome Editing and Human Reproduction (London: Nuffield Council on Bioethics, 2018).
文章頭圖及封面圖片：人類基因組編輯國際峰會大會現(xiàn)場（攝影 劉新星）
附：原文
On Human Genome Editing II
Statement by the Organizing Committee of the
Second International Summit on Human Genome Editing
November 29, 2018
In December 2015, the U.S. National Academy of Sciences and U.S. National Academy of Medicine, the Royal Society of the United Kingdom, and the Chinese Academy of Sciences hosted an international summit in Washington, D.C., to discuss scientific, ethical, and governance issues associated with human genome editing. At its conclusion, the summit organizing committee released a statement identifying areas of research and clinical use that could proceed within current regulatory and governance protocols. The committee also stated that it would be irresponsible to proceed with any clinical use of heritable "germline" editing at that time. Further, it called for continued international discussion of potential benefits, risks, and oversight of this rapidly advancing technology.
As part of their commitment to fostering in-depth and international discussion about human genome editing, the Academy of Sciences of Hong Kong, the Royal Society of the United Kingdom, and the U.S. National Academy of Sciences and U.S. National Academy of Medicine organized the Second International Summit on Human Genome Editing in Hong Kong to assess the evolving scientific landscape, possible clinical applications, and attendant societal reactions to human genome editing. While we, the organizing committee of the second summit, applaud the rapid advance of somatic gene editing into clinical trials, we continue to believe that proceeding with any clinical use of germline editing remains irresponsible at this time.
Human Genome Editing Research
Basic and preclinical research is rapidly advancing the science of somatic and germline genome editing. Better understanding and design of genome editing techniques, including base editing, have produced significant increases in efficiency and precision while greatly reducing off-target events. As was anticipated, somatic genome editing is now being tested in patients.
Making changes in the DNA of embryos or gametes could allow parents who carry disease-causing mutations to have healthy, genetically related children. However, heritable genome editing of either embryos or gametes poses risks that remain difficult to evaluate. Concerns persist that changes may be made in only some cells of early-stage embryos, leaving unedited cells to perpetuate a disease. Germline editing could produce unintended harmful effects for not just an individual but also for that individual’s descendants. Changes to a particular trait may have unanticipated effects on other traits that could vary from person to person and in response to environmental influences.
The variability of effects produced by genetic changes makes it difficult to conduct a thorough evaluation of benefits and risks. Nevertheless, germline genome editing could become acceptable in the future if these risks are addressed and if a number of additional criteria are met. These criteria include strict independent oversight, a compelling medical need, an absence of reasonable alternatives, a plan for long-term follow-up, and attention to societal effects. Even so, public acceptability will likely vary among jurisdictions, leading to differing policy responses.
The organizing committee concludes that the scientific understanding and technical requirements for clinical practice remain too uncertain and the risks too great to permit clinical trials of germline editing at this time. Progress over the last three years and the discussions at the current summit, however, suggest that it is time to define a rigorous, responsible translational pathway toward such trials.
A Proposed Translational Pathway
A translational pathway to germline editing will require adhering to widely accepted standards for clinical research, including criteria articulated in genome editing guidance documents published in the last three years.[1] Such a pathway will require establishing standards for preclinical evidence and accuracy of gene modification, assessment of competency for practitioners of clinical trials, enforceable standards of professional behavior, and strong partnerships with patients and patient advocacy groups.
Report of Clinical Use of Germline Editing
At this summit we heard an unexpected and deeply disturbing claim that human embryos had been edited and implanted, resulting in a pregnancy and the birth of twins. We recommend an independent assessment to verify this claim and to ascertain whether the claimed DNA modifications have occurred. Even if the modifications are verified, the procedure was irresponsible and failed to conform with international norms. Its flaws include an inadequate medical indication, a poorly designed study protocol, a failure to meet ethical standards for protecting the welfare of research subjects, and a lack of transparency in the development, review, and conduct of the clinical procedures.
An Ongoing International Forum
The organizing committee calls for an ongoing international forum to foster broad public dialogue, develop strategies for increasing equitable access to meet the needs of underserved populations, speed the development of regulatory science, provide a clearinghouse for information about governance options, contribute to the development of common regulatory standards, and enhance coordination of research and clinical applications through an international registry of planned and ongoing experiments.
In addition to the establishment of an international forum, the organizing committee calls upon national academies and learned societies of science and medicine around the world to continue the practice of holding international summits to review clinical uses of genome editing, to gather diverse perspectives, to inform decisions by policymakers, to formulate recommendations and guidelines, and to promote coordination among nations and jurisdictions.
[1] See, for example, National Academies of Sciences, Engineering, and Medicine, Human Genome Editing: Science, Ethics, and Governance (Washington, DC: The National Academies Press, 2017) and Nuffield Council on Bioethics, Genome Editing and Human Reproduction (London: Nuffield Council on Bioethics, 2018).
Organizing Committee
David Baltimore[1,2] (committee chair)
President Emeritus and Robert Andrews Millikan Professor of Biology
California Institute of Technology
United States
Alta Charo[2]
Warren P. Knowles Professor of Law and Bioethics
University of Wisconsin, Madison
United States
George Q. Daley[2]
Dean of the Faculty of Medicine and Caroline Shields Walker Professor of Medicine
Harvard Medical School
United States
Jennifer A. Doudna[1,2]
Investigator, Howard Hughes Medical Institute; and
Professor, Department of Molecular and Cell Biology and Department of Chemistry
University of California, Berkeley
United States
Kazuto Kato
Professor of Biomedical Ethics and Public Policy
Graduate School of Medicine
Osaka University
Japan
Jin-Soo Kim
Director of Center for Genome Engineering
Institute for Basic Science
Seoul National University
South Korea
Robin Lovell-Badge[3]
Senior Group Leader
The Francis Crick Institute; and
Special Visiting Professor
University of Hong Kong
United Kingdom
Jennifer Merchant
Professor of Legal and Political Institutions
Université de Paris II (Panthéon-Assas)
France
Indira Nath
Visiting Professor, Bio-Support Unit
Department of Biotechnology
All India Institute of Medical Sciences (AIIMS); and
Former Raja Ramanna Fellow and Emeritus Professor
National Institute of Pathology
India
Duanqing Pei
Professor and Director General
Guangzhou Institutes of Biomedicine and Health
Chinese Academy of Sciences
China
Matthew Porteus
Associate Professor of Pediatrics
Division of Stem Cell Transplantation and Regenerative Medicine
Stanford University
United States
John Skehel[3]
Emeritus Scientist
The Francis Crick Institute
United Kingdom
Patrick Tam[3]
Deputy Director and Head, Embryology Research Unit
Children's Medical Research Institute;
Senior Principal Research Fellow
National Health and Medical Research Council (NHMRC) of Australia;
Professor, School of Medical Sciences, Faculty of Medicine and Health
The University of Sydney; and
Mok Hing-Yiu Distinguished Visiting Professor
School of Biomedical Sciences
University of Hong Kong
Australia
Xiaomei Zhai
Professor and Executive Director, Centre for Bioethics
Chinese Academy of Medical Sciences and Peking Union Medical College
China
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[1] Member, U.S. National Academy of Sciences
[2] Member, U.S. National Academy of Medicine
[3] Fellow, The Royal Society
