HONG KONG—The Day After. Two hundred and sixty accredited reporters had dwindled to about a dozen. A conference livestream that peaked at 1.8 million viewers worldwide had dwindled to a much, much smaller figure. And He Jiankui—the researcher at the center of a media and medical firestorm—was back in Shenzhen, China, facing an uncertain future.

Obliged to sum up the events of an extraordinary week, the organizing committee of the second Human Genome Editing summit issued a closing statement that criticized the unprecedented clinical work that has led to the reported birth of twins with an edited genome and called for a suspension of any further clinical trials of germline editing.

“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,” was the major headline.

Nobel Laureate David Baltimore read out the statement on behalf of the 14 members of the committee, which includes CRISPR pioneer Jennifer Doudna (UC Berkeley), Robin Lovell-Badge (Crick Institute), Sir John Skehel (Royal Society), George Daley (Dean, Harvard Medical School), ethicist Alta Charro (University Wisconsin), and gene editing researchers Matthew Porteus (Stanford) and Jin-Soo Kim (Seoul National University).

Breaking News

The committee called the work of Dr. He on the birth of germline-edited twins “deeply disturbing” and called for an independent assessment “to verify this claim and to ascertain whether the claimed DNA modifications have occurred,” Baltimore said.

“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.”

The concerns expressed in the statement have been buttressed by other leading figures in biomedical research industry, who reacted swiftly to the germline editing news.

The Director of the NIH, Francis Collins, issued a statement expressing deep concern about the reports: The NIH does not support the use of gene-editing technologies in human embryos. The reports exhibited “a deeply disturbing willingness by Dr. He and his team to flout international ethical norms. The project was largely carried out in secret, the medical necessity for inactivation of CCR5 in these infants is utterly unconvincing, the informed consent process appears highly questionable, and the possibility of damaging off-target effects has not been satisfactorily explored.”

Collins said the need for “a binding international consensus on setting limits for this kind of research…has never been more apparent. Without such limits, the world will face the serious risk of a deluge of similarly ill-considered and unethical projects. Should such epic scientific misadventures proceed, a technology with enormous promise for prevention and treatment of disease will be overshadowed by justifiable public outrage, fear, and disgust.”

In an interview with Biocentury, FDA Commissioner Scott Gottlieb said: “Governments will now have to react” taking into account that “the scientific community failed to convincingly assert, in this case, that certain conduct must simply be judged as over the line.”

“The response from the scientific community has been far too slow and far too tepid, and the credibility of the community to self-police has already been damaged,” Gottlieb said, although given that the entire community has only known of this clinical work for a few days, it’s not clear what the response should have been.

Deep Concerns

The HGE Committee statement said there were many lingering “deep concerns” over the science and ethics of germline genome editing, but noticeably did not call for a moratorium on genome-editing research.

“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.”

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 committee also stressed the need to formulate a translational pathway to germline editing. This would 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.”

The committee also called for “an ongoing international forum to foster broad public dialogue, develop strategies for increasing equitable access to meet the needs of under-served 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.”

Conferences such as CRISPRcon have performed a valuable function in expanding diversity. A couple of conference participants suggested that the United Nations should be involved in genome regulation, but the committee did not go that far.

A third Human Genome Editing summit will be held in London, it was announced, probably in 2021.