THE EMERGING FIELD
OF HUMAN NEURAL
SCIENCE, ETHICS, AND GOVERNANCE
Committee on Ethical, Legal, and Regulatory Issues Associated with
Neural Chimeras and Organoids
Committee on Science, Technology, and Law
Policy and Global Affairs
A Consensus Study Report of
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This activity was supported by contracts from the National Institutes of Health (Sponsor Award Number HHSN263201800029I/75N98019F00861) and The Dana Foundation. This Project has been funded in whole or in part with federal funds from the National Institutes of Health, Department of Health and Human Services, under Contract No. HHSN263201800029I. Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.
International Standard Book Number-13: 978-0-309-30336-1
International Standard Book Number-10: 0-309-30336-2
Digital Object Identifier: https://doi.org/10.17226/26078
Library of Congress Control Number: 2021938584
Cover image: High-magnification view of a neural organoid modeling early stages of development of the cerebral cortex. Image courtesy of Silvia Velasco and Paola Arlotta, Department of Stem Cell and Regenerative Biology, Harvard University.
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Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2021. The Emerging Field of Human Neural Organoids, Transplants, and Chimeras: Science, Ethics, and Governance. Washington, DC: The National Academies Press. https://doi.org/10.17226/26078.
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COMMITTEE ON ETHICAL, LEGAL, AND REGULATORY ISSUES ASSOCIATED WITH NEURAL CHIMERAS AND ORGANOIDS
BERNARD LO (NAM), Professor Emeritus, University of California, San Francisco and President and CEO Emeritus, The Greenwall Foundation.
JOSHUA R. SANES (NAS), Jeff C. Tarr Professor of Molecular and Cellular Biology and Paul J. Finnegan Family Director, Center for Brain Science, Harvard University
PAOLA ARLOTTA, Chair, Harvard Department of Stem Cell and Regenerative Biology and Golub Family Professor of Stem Cell and Regenerative Biology, Harvard University
R. ALTA CHARO (NAM), Warren P. Knowles Professor Emerita of Law and Bioethics, University of Wisconsin Law School
JOHN H. EVANS, Professor, Tata Chancellor’s Chair in Social Sciences, Associate Dean of Social Sciences, and Co-director of the Institute for Practical Ethics, University of California, San Diego
FRED H. GAGE (NAS/NAM), President and Professor, Laboratory of Genetics, and Vi and John Adler Chair for Research on Age-Related Neurodegenerative Disease, Salk Institute for Biological Studies
HENRY T. GREELY, Deane F. and Kate Edelman Johnson Professor of Law, Professor, by courtesy, of Genetics, Stanford School of Medicine, and Director, Center for Law and the Biosciences, Stanford University
PATRICIA A. KING (NAM), Professor Emerita, Georgetown University Law Center
WILLIAM T. NEWSOME (NAS), Harman Family Provostial Professor of Neurobiology, Stanford University School of Medicine, and Vincent V.C. Woo Director, Wu Tsai Neurosciences Institute, Stanford University
SALLY TEMPLE, Scientific Director, Principal Investigator, and Co-Founder, Neural Stem Cell Institute
A. LAWRENCE ZIPURSKY (NAS), Distinguished Professor, Department of Biological Chemistry, University of California, Los Angeles, and Investigator, Howard Hughes Medical Institute
ANNE-MARIE MAZZA, Study Director and Senior Director, Committee on Science, Technology, and Law
STEVEN KENDALL, Program Officer, Committee on Science, Technology, and Law
ANITA EISENSTADT, Program Officer, U.S. Science and Innovation Policy
VERN DUNN, Program Officer, U.S. Science and Innovation Policy
DOMINIC LOBUGLIO, Senior Program Assistant, Committee on Science, Technology, and Law
SARAH CARTER, Consultant Writer
COMMITTEE ON SCIENCE, TECHNOLOGY, AND LAW
DAVID BALTIMORE (NAS/NAM), President Emeritus and Robert Andrews Millikan Professor of Biology, California Institute of Technology
DAVID S. TATEL, Judge, U.S. Court of Appeals for the District of Columbia Circuit
JOE S. CECIL, Senior Fellow, Civil Justice Research Initiative, University of California, Berkeley School of Law
ERWIN CHEMERINSKY, Dean and Jesse H. Choper Distinguished Professor, University of California, Berkeley School of Law
ELLEN WRIGHT CLAYTON (NAM), Professor of Law and Professor of Health Policy, Vanderbilt University Medical Center
JOHN S. COOKE, Director, Federal Judicial Center
JOHN DABIRI, Centennial Professor of Aeronautics and Mechanical Engineering, California Institute of Technology
JENNIFER EBERHARDT (NAS), Professor of Psychology, Stanford University
FEI-FEI LI (NAE/NAM), Sequoia Capital Professor, by courtesy, of Operations, Information and Technology, Stanford University
JUDITH MILLER, Independent Consultant
MARTHA MINOW, 300th Anniversary University Professor, Harvard Law School
KIMANI PAUL-EMILE, Professor of Law, Fordham University Law School
NATALIE RAM, Associate Professor of Law, University of Maryland Francis King Carey School of Law
LISA RANDALL (NAS), Professor of Theoretical Physics, Harvard University
PAUL M. ROMER, Professor of Economics and Director, The Urbanization Project, New York University
WILLIAM B. SCHULTZ, Partner, Zuckerman Spaeder LLP
JOSHUA SHARFSTEIN (NAM), Vice Dean and Professor, Johns Hopkins Bloomberg School of Public Health
SUSAN S. SILBEY, Leon and Anne Goldberg Professor of Humanities, Professor of Sociology and Anthropology, and Professor of Behavioral and Policy Sciences, Massachusetts Institute of Technology
SRI SRINIVASAN, Chief Judge, U.S. Court of Appeals for the District of Columbia Circuit
GREGORY STONE, Partner, Munger, Tolles & Olson LLP
SUSAN WESSLER (NAS), Neil and Rochelle Campbell Presidential Chair for Innovation in Science Education, University of California, Riverside, and Home Secretary, U.S. National Academy of Sciences
ANNE-MARIE MAZZA, Senior Director
STEVEN KENDALL, Program Officer
DOMINIC LOBUGLIO, Senior Program Associate
More than any other organ, the brain gives human beings their unique identities. The complexity of the human brain has perplexed researchers, and its central role in the mystery termed consciousness continues to challenge the boundaries between science and philosophy. Conversely, devastating neurological and psychiatric diseases and disorders not only cause untold suffering but can also rob people of their identity. For many of these diseases, treatments are completely unavailable, and for others they are hopelessly inadequate.
Research over the past several decades has greatly advanced understanding of the brain and begun to provide new therapeutic approaches to brain diseases. However, progress in this area is stymied by the practical and ethical difficulties of studying the human brain and by serious limitations of existing tools and models. In response, researchers have worked to develop new models that promise a deeper understanding of the human brain and new treatments for brain disorders. These new models include human neural organoids, transplants of human stem cells into nonhuman animal brains, and human neural chimeras. However, as models of the brain improve to better reflect the characteristics of actual human brains, they also raise profound ethical questions. It has become clear that in using these models to advance understanding of the brain, it will be necessary to pay attention to what lessons they might teach about consciousness and what it means to be human.
For the past year, at the request of the National Institutes of Health and the Dana Foundation and under the auspices of the National Academies of Sciences, Engineering, and Medicine’s Committee on Science, Technology, and Law, we co-chaired a committee of scientists, ethicists, and legal scholars that explored recent scientific advances and ethical and governance issues associated with hu-
man neural organoids, transplants, and chimeras. The committee heard from numerous experts and reviewed relevant scientific literature, religious scholarship, and current laws and policies. We are grateful for the individuals who spoke to and engaged in thoughtful discussions with the committee. Their expertise contributed greatly to the committee’s deliberations. In particular, interactions among biomedical scientists, ethicists, religious scholars, and legal experts provided the committee with important insights.
We are deeply indebted to the committee members for the time and effort they devoted to reading and reviewing background materials; preparing for discussions with invited experts; attending virtual meetings; and engaging in thoughtful, critical analysis and discussion with each other. This report is a reflection of their commitment to understanding the issues under consideration.
We greatly appreciate as well the efforts of study director Anne-Marie Mazza and study staff Steven Kendall, Anita Eisenstadt, Vern Dunn, and Dominic LoBuglio and of consultant writer, Sarah Carter.
Bernard Lo and Joshua R. Sanes,
Acknowledgment of Presenters
The committee gratefully acknowledges the thoughtful contributions of the following individuals who made presentations before the committee:
Megan Albertelli, Stanford University; Mark Barnes, Ropes & Gray LLP; Allan Basbaum (NAS/NAM), University of California, San Francisco; Valerie Bonham, Ropes & Gray LLP; Emery Brown (NAS/NAM/NAE), Massachusetts Institute of Technology; I. Glenn Cohen, Harvard Law School; Charles Camosy, Fordham University; David DeGrazia, George Washington University; Frans B. M. de Waal, Emory University; Brian Edlow, Massachusetts General Hospital; Nita Farahany, Duke University School of Law; Guoping Feng, Massachusetts Institute of Technology; Steven Goldman, University of Rochester Medical Center; Steven E. Hyman (NAM), Harvard University and Dana Foundation; Insoo Hyun, Case Western Reserve University; Eva Jablonka, Tel-Aviv University; Kathleen Hall Jamieson (NAS), University of Pennsylvania; Christof Koch, Allen Institute for Brain Science; Arnold Kriegstein (NAM), University of California, San Francisco; Margaret Landi, GlaxoSmithKline; John Loike, Columbia University; Robin Lovell-Badge, The Francis Crick Institute; Brad Margus, Cerevance; Sergiu Pasca, Stanford University; James Peterson, Roanoke College; Mu-Ming Poo (NAS), Institute of Neuroscience of the Chinese Academy of Sciences; Margaret Foster Riley, University of Virginia School of Law; Dietram Scheufele, University of Wisconsin–Madison; Bjoern Schwer, University of California, San Francisco; Anil Seth, University of Sussex; Sarra Tlili, University of Florida; Joyce Tischler, Lewis & Clark Law School; Gordana Vunjak-Novakovic (NAE/NAM), Columbia University; and Carrie Wolinetz, National Institutes of Health.
Acknowledgment of Reviewers
This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.
We thank the following individuals for their review of this report:
Charles Camosy, Fordham University; Patricia Churchland, University of California, San Diego; Ellen Wright Clayton (NAM), Vanderbilt University; I. Glenn Cohen, Harvard University; Jonathan Flint, University of California, Los Angeles; Michael Goldberg (NAS), Columbia University; Steven Goldman, University of Rochester Medical Center; Gillian Hue, Emory University; Insoo Hyun, Case Western Reserve University; Madeline Lancaster, University of Cambridge; Margaret Landi, GlaxoSmithKline; James Peterson, Roanoke College; Alex Pollen, University of California, San Francisco; Anil Seth, University of Sussex; Hongjun Song (NAM), University of Pennsylvania; and Robert Streiffer, University of Wisconsin–Madison.
Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report nor did they see the final draft before its release. The review of this report was overseen by Wylie Burke (NAM), University of Washington, and Thomas D. Albright (NAS), Salk Institute for Biological Studies. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.