Paris Conference

on Risks from Mirror Life

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12-13th June 2025 at Institut Pasteur

The Event

In 1847, Louis Pasteur was the first to identify the fundamental role of molecular chirality in biology. By examining crystals isolated from wine, he realised that many biological molecules can occur in mirror-image forms. Almost 200 years later, at the institution he founded, experts gathered to discuss the profound implications of that discovery in the context of modern synthetic biology.

A late 2024 article in Science described potential risks from the creation of mirror bacteria—synthetic bacteria in which all biomolecules are the mirror-image versions of natural ones. The analysis, authored by a group including many who had previously hoped to develop such organisms in the coming decades, explains how the risks of mirror bacteria could be unprecedentedly severe and calls for further discussion to chart a responsible path forward.

This Conference was the first in a series of international meetings bringing together a wide range of stakeholders to discuss and address the feasibility and risks of efforts to develop mirror life. The Conference began on 12th June with a publicly-streamed Symposium that shared the current state of scientific understanding on these topics with a broad audience. On 13th June, a series of expert workshops were held to begin addressing outstanding questions.

The discussions at the Conference are summarized in a meeting report here.

Recommendations

Based on the discussions at the Conference, the following recommendations are offered by the Conference Steering Committee to guide further efforts to manage the risks of mirror organisms:

Researchers should refrain from pursuing the creation of mirror organisms, and both public and private funders should make clear that they will not support research aimed at this goal.
Work should start now to develop frameworks for governing key technical milestones on the pathways to mirror life, with consideration of hard and soft law at institutional, national, and international levels. Input should be sought from governments, scientists, funding bodies, standard-setting institutions, international organizations, communicators, social scientists, civil society networks and publics, ethicists, and industry groups.
Efforts to mitigate the risks of mirror organisms should preserve scientific freedom and the potential benefits of life-science research to the maximum extent possible.
Further research should be conducted into the risks and potential benefits of mirror organisms, for determining the scale of risk and informing future preparedness, detection, and response efforts, as long as this research does not itself advance the creation of mirror organisms and is performed in an open and transparent fashion.

Symposium
Speakers

David Bikard, PhD

Head of the Synthetic Biology Group, Institut Pasteur

Dr. David Bikard is the head of the Synthetic Biology Group at the Institut Pasteur in Paris, France. Dr. Bikard obtained an engineering degree from AgroParisTech, as well as a master degree and PhD from Paris Diderot University for his work performed at the Institut Pasteur on the integron bacterial recombination system. He then joined the laboratory of Luciano Marraffini at the Rockefeller University as a postdoctoral fellow, where he started to work on CRISPR systems. His work led to him becoming the founder and CSO of the company Eligo Biosciences. Now, Dr. Bikard is a young investigator at the Institut Pasteur in the department of Microbiology, where he started his group in 2014. The Synthetic Biology Group investigates genetic systems that emerge as a result of the arms race between bacteria and bacteriophages, and how these systems can be harnessed as novel biotechnological tools to better understand and fight pathogenic bacteria.

Associate Professor in Science & International Security in the Department of War Studies and the Department of Global Health & Social Medicine at King’s College London

Filippa Lentzos, PhD

Dr Filippa Lentzos is a Reader (Associate Professor) in Science & International Security at King’s College London. She is cross-appointed to the Department of War Studies and the Department of Global Health & Social Medicine, and she leads several research projects, including on global biolabs, disinformation, responsible science and BWC verification.

Outside King’s, she is an Associate Senior Researcher at the Stockholm International Peace Research Institute (SIPRI) in Sweden, and a Non-Resident Scholar at the James Martin Center for Nonproliferation Studies (CNS) in the United States. Dr. Lentzos chairs the WHO Technical Advisory Group on the responsible use of the life sciences and dual-use research (WHO RULS DUR), and she is a member of the WHO Health Security Interface – Technical Advisory Group (WHO HSI-TAG). She is also a rostered expert for the UN Secretary-General’s Mechanism for Investigation of Alleged Use of Chemical or Biological Weapons (UNSGM), and she serves as the NGO Coordinator for the Biological Weapons Convention.

Professor, leader of the JCVI Synthetic Biology Group, and La Jolla, CA Campus Director at the J. Craig Venter Institute

John Glass, PhD

Dr. John Glass is a Professor at the J. Craig Venter Institute (JCVI) where he leads the Synthetic Biology and Bioenergy Group. He is also Director of the JCVI La Jolla campus. Dr. Glass’s research team created a minimal bacterial cell with a genome comprising only the essential genes necessary for life in rich laboratory media called JCVI-syn3.0. This simplest of all microbes encodes genes from the caprine pathogen, Mycoplasma mycoides subspecies capri. Dr. Glass’s JCVI team as well as more than 80 other research teams are using this cell to investigate the first principles of cellular life. Additionally, from the lessons learned through building a synthetic cell with a minimal gene set, the JCVI synthetic biologists hope to design and create cells with extraordinary properties that address human needs in medicine, bioenergy, and the environment. Dr. Glass also directs JCVI teams that are investigating how viruses defeat antiviral components of the human innate immune system, developing a new treatment for type I diabetes based on the human skin microbiome, developing new methods for synthesis of human artificial chromosomes, and constructing large genome phage that encode gene sets to enable their use as antibacterial therapeutics.

Dr. Glass earned his undergraduate and doctoral degrees from the University of North Carolina at Chapel Hill. Before joining the JCVI in 2003, he worked in the Infectious Diseases Research Therapeutic Area at the pharmaceutical company Eli Lilly from 1998-2003.

David Relman, MD

Professor in Medicine, Professor of Microbiology & Immunology at Stanford University

David A. Relman, MD is the Thomas C. and Joan M. Merigan Professor in Medicine, Professor of Microbiology & Immunology, and Senior Fellow at the Freeman Spogli Institute for International Studies at Stanford University. He is also Chief of Infectious Diseases at the Veterans Affairs Palo Alto Health Care System in Palo Alto, California.

Dr. Relman was an early pioneer in the modern study of the human indigenous microbiota (microbiome). Most recently, his work has focused on human microbial community stability, resilience, and evolution in the face of experimental perturbation, such as antibiotic exposure. Previous work included the development of methods for pathogen discovery and the identification of several historically important and novel microbial disease agents.

He has advised the U.S. Government on emerging infectious diseases, human-microbe interactions, and future biological threats. He served as a founding member of the National Science Advisory Board for Biosecurity, Chair of the Boards of Scientific Counselors at the National Institute for Dental and Craniofacial Research and National Center for Biotechnology Information, and as President of the Infectious Diseases Society of America. He is a Fellow of the American Academy of Microbiology, a Member of the National Academy of Medicine, and a Member of the American Academy of Arts & Sciences. From May 2024 to January 2025, he served as Senior Advisor in the Office of Pandemic Preparedness and Response Policy at the White House.

Deepa Agashe, PhD

Associate Professor, National Centre for Biological Sciences, Bangalore, India

Deepa Agashe is an Associate Professor at the National Centre for Biological Sciences (NCBS), Bengaluru, where she has led a research group since 2012. Dr. Agashe received her PhD from the University of Texas at Austin in 2009, and conducted postdoctoral research at Harvard University before returning to India. Her team uses experimental and bioinformatics approaches to understand the processes and mechanisms underlying adaptive evolution, using insect and bacterial models. Their work helps explain how species colonize new habitats, how selection on translation rate and accuracy has shaped bacterial genomes and bacterial evolution, and the consequences of skewed mutation spectra.
Dr. Agashe’s work is supported by grants from the DBT/Wellcome Trust India Alliance. She received a Women Research Excellence Award from the Scientific and Engineering Research Board (SERB) of India, and a Faculty Excellence award from the Society for Molecular Biology and Evolution. She has previously served as the Vice President of the American Society of Naturalists, is an elected Fellow of the Indian Academy of Science, and serves as an editor for several journals in the field.

Yasmine Belkaid, PhD

President, Institut Pasteur

Prof. Yasmine Belkaid is the President of the Institut Pasteur (Paris) and the head of the Metaorganism laboratory at the Institut Pasteur.

She obtained her Master in Biochemistry at the University of Science and Technology Houari Boumediene in Algiers, Algeria and her PhD from the Institut Pasteur in Paris, France.

Her work explores fundamental mechanisms that regulate tissue homeostasis and host immune responses and uncovered key roles for the microbiota and dietary factors in the control of immunity and protection to pathogens. It also explores the role of the immune system in organismal remodeling and the impact of infections on the mother-child dyad.

Prof. Belkaid is a member of the US National Academy of Sciences, the American Academy of Arts and Sciences, the National Academy of Medicine and the Académie des Sciences. She is the recipient of numerous awards including the Lurie Prize in Biomedical Sciences, the Emil von Behring Prize, the Sanofi-Institut Pasteur Award, the Robert Koch Award, and the AAI Excellence in Mentoring Award.

Symposium

Agenda for June 12th

15:00

Introductory remarks

David Bikard, PhD
Head of the Synthetic Biology Group, Institut Pasteur

15:10

The international conversation on mirror life

Filippa Lentzos, PhD
Associate Professor in Science & International Security in the Department of War Studies and the Department of Global Health & Social Medicine at King’s College London

15:40

Pathways to mirror life

John Glass, PhD
Professor, leader of the JCVI Synthetic Biology Group, and La Jolla, CA Campus Director at the J. Craig Venter Institute

16:10

Break

16:30

Mirror bacteria and the environment

Deepa Agashe, PhD
Associate Professor, National Centre for Biological Sciences, Bangalore, India

17:00

Host encounters with mirror bacteria

David Relman, MD
Professor in Medicine, Professor of Microbiology & Immunology at Stanford University

17:30

Closing Remarks

David Relman, MD & David Bikard, PhD

Building on a Century of Breakthroughs

The Institut Pasteur has shaped some of the most consequential advances in modern biology, inspired by Louis Pasteur’s humanist ideals. Hosting this dialogue here reflects both the importance of the questions at stake and our shared commitment to ensuring scientific efforts benefit all of humanity.

Pasteur’s Mirror

In 1847 Louis Pasteur, a young chemist freshly graduated from the prestigious École normale supérieure, set to work on the problem posed by German physicist Eilhard Mitscherlich, namely: why do sodium ammonium paratartrate and tartrate–two seemingly identical chemical substances–affect polarized light differently? He discovered that these molecules are mirror images—structurally distinct, but fundamentally related, like left and right hands. His hand-drawn crystals mark the beginning of our understanding of the importance of chirality for life—and the first glimpse of what would become mirror biology.

Schéma des cristaux de paratartrate (Louis Pasteur, 1848).

Formes cristallines du dextroracémate et du lévoracémate (Louis Pasteur, 1848)

Organizers

This event was organized in collaboration between the Institut Pasteur and the Mirror Biology Dialogues Fund, under the leadership of the Conference’s steering committee members.

Conference Steering Committee