Clinical trials involving the editing of genes in sperm, eggs and early-stage embryos could be permitted under certain conditions, the National Academies of Sciences and the National Academy of Medicine recommended Tuesday in a long-awaited report.
Once technical questions are resolved, clinical trials could start with extensive oversight, the report said. But the report urged limiting trials to the “most compelling circumstances,” such as when no other treatment exists, the condition is very serious, and the genes in question are well known to cause a particular disease.
Gene editing offers the possibility of treating many diseases, and there are already trials or advanced research under way to use the techniques to try to cure individuals with HIV, sickle cell anemia and cancer. But adjustments made to the human germ line—eggs, sperm and embryos—don’t just change the health of a single person; they can be passed on to any future offspring.
For that reason, a gene-editing trial involving the germ line would have to include oversight not only of people participating in the trial but also following the long-term health of future generations, presumably including people who haven’t been born yet and never consented to being in a clinical trial.
The report was the result of work by an advisory committee, which convened more than a year ago at the request of the nonprofit National Academies of Sciences and the National Academy of Medicine. The committee studied the ethical, scientific and regulatory questions raised by gene editing, and the report weighs in on some of the most difficult and emotionally charged issues surrounding the technology.
The idea raises difficult ethical questions. Gene editing is still a novel technology and can have unintended, potentially harmful, consequences that would then be passed on to future generations.
For years, such questions remained in the realm of speculation. But the introduction of a new gene-editing approach called Crispr-Cas9, and its rapid adoption by scientists due to its comparative ease and lower cost, makes the idea feasible in a way it hasn’t been before.
“The technology has moved significantly even during the last year when we were studying the issue,” said Richard O. Hynes, co-chair of the committee that wrote the report and a professor at the Massachusetts Institute of Technology in Cambridge, Mass. “Things that were not feasible became feasible.”
The report’s cautious words aside, the findings represent a significant milestone in thinking about the topic because of the committee’s prestige and its suggestion that there is a potential ethical path to follow once the technology is further developed.
Scientists continue to wrestle with what limits to impose on using Crispr inside the lab. In 2015, a group of researchers and thinkers published a paper in the journal Science suggesting that scientists should publicly discourage preliminary experiments using Crispr to modify cells in sperm or eggs and urging greater openness in reporting and discussing research and results. Congress has also weighed in; it passed a provision that is in effect until at least April of this year that effectively bars U.S. authorities from reviewing proposals for clinical trials involving gene editing of the human germ line.
Dr. Hynes said that, despite the many concerns, he doesn’t believe such gene editing should be prohibited. He said any risks must be weighed against the possible benefit of helping “a patient who is sitting in front of you with a potential problem you may be able to solve.”
“I wouldn’t prohibit it,” he said. “I would regulate it tightly.”
