Scientists could be allowed to make modifications in human DNA that can be passed down through subsequent generations, the National Academy of Sciences and the National Academy of Medicine say.
Such a groundbreaking step should only be considered after more research and then only be conducted under tight restrictions, the academies write in a highly anticipated report released Tuesday. Such work should be reserved to prevent serious diseases and disabilities, it says.
The academies determined that new gene-editing techniques had made it reasonable to pursue such controversial experiments down the road, though not quite yet.
"It is not ready now, but it might be safe enough to try in the future," R. Alta Charo, a bioethicist at the University of Wisconsin-Madison who co-chaired the committee, said. "And if certain conditions are met, it might be permissible to try it."
That conclusion counters a long-standing taboo on making changes in genes in human sperm, eggs or embryos because such alterations would be inherited by future generations. That taboo has been in place partly because of fears that mistakes could inadvertently create new diseases, which could then become a permanent part of the human gene pool.
Another concern is that this kind of genetic engineering could be used to make genetic modifications for nonmedical reasons.
For example, scientists could theoretically try to create designer babies, in which parents attempt to select the traits of their children to make them smarter, taller, better athletes or to have other supposedly superior attributes.
Nothing like that is currently possible. But even the prospect raises fears about scientists essentially changing the course of evolution and creating people who are considered genetically superior, conjuring up the kind of dystopian future described in movies and books like Aldous Huxley's Brave New World.
"These kinds of scenarios used to be science fiction; they used to be seen as far-off hypotheticals," says Marcy Darnovsky, who runs the Center for Genetics and Society, a genetic watchdog group. "But actually, right now, I think they're urgent social justice questions."
She says, "we're going to be creating a world in which the already privileged and affluent can use these high-tech procedures to make children who either have some biological advantages" or are perceived to have biological advantages. "And the scenario that plays out is not a pretty one."
But Charo says the report clearly states that any attempt to create babies from sperm, eggs or embryos that have had their DNA edited could only be tried someday under very tightly controlled conditions and only to prevent devastating medical disorders.
"We said, 'Use it for serious diseases and serious conditions only — period,'" Charo says. "We simply said, 'No enhancement.' "
But Darnovsky is skeptical that line will hold. "I don't think there's any way to keep that genie in the bottle," he says.
The report, however, was praised by many scientists.
"It's important to be extraordinarily cautious on technologies that could leave a permanent mark on the human population for all generations to come," says Eric Lander, who runs the Broad Institute at the Massachusetts Institute of Technology and Harvard University. "But it's important to try to help people. I think they've been very thoughtful about how you should balance those things."
The report acknowledges that it may be difficult in the future to draw a line between using gene-editing to prevent or treat disease and using it for enhancement. Gene-editing designed to prevent or treat the muscle disease muscular dystrophy, for example, could theoretically be used to try to make healthy people stronger.
Prominent Harvard geneticist George Church agrees. "The report is very clearly broad," he says. "It could include a lot of things people consider enhancement. I think it will be case by case and there will be some people will be consider enhancement that some people will consider preventive medicine."
For example, if scientists figure out how to makes changes that boost thinking abilities to stave off dementia in Alzheimer's patients by making them slightly above average or considerably above average, he says, "that might be considered enhancement or it might be considered preventive medicine."
Scientists have been able to edit the DNA in the cells of humans and other creatures for decades. But the academies commissioned the report after scientists developed powerful new gene-editing techniques in recent years, such as CRISPR-Cas9, that make it much easier and faster.
That raised the possibility that gene editing might be used to treat many diseases and possibly even to prevent many devastating disorders from occurring in the first place by editing out genetic mutations in sperm, eggs and embryos. That could potentially prevent a wide range of diseases, including breast cancer, Tay-Sachs, sickle cell anemia, cystic fibrosis and Huntington's disease.
As a result, the academies assembled a 21-member committee of scientists, bioethicists, lawyers, patient advocates, biotech entrepreneurs and others to conduct a far-reaching investigation that involved more than year of study.
The resulting report stresses that because the technology is so new, it would be unsafe for anyone to even begin studies to try to create babies from sperm, eggs or embryos that have had their DNA edited before conducting much more research.
The committee also says no clinical trials of gene editing should be allow unless:
- there is no "reasonable alternative" to prevent a "serious disease or condition"
- it has been "convincingly demonstrated" that genes being editing "cause" or "strongly predispose" people to the disease or condition
- gene editing is only aimed at "converting such genes to versions" that are "known to be associated with ordinary health"
- sufficient preliminary research has been done on "risks and potential health benefits"
- there would be "ongoing, rigorous oversight" of the studies of the "effects of the procedures on the health and safety of the participants" as well as "comprehensive plans for long-term, multi-generational follow-up"
- there is "maximum transparency consistent with patient privacy" and "continued reassessment of both and health and societal benefits and risks"
- there are "reliable oversight mechanisms to prevent extension to uses other than preventing a serious disease or condition."
"It would be essential for this research to be approached with caution, and for it to proceed with broad public input," the 261-page report states.
The report notes that the Food and Drug Administration is barred from reviewing "research in which a human embryo is intentionally created or modified to include a heritable genetic modification." Federal funding of such research is also prohibited.
Many other countries have signed an international convention prohibiting this kind of gene editing.
But the report aims to provide guidance for those countries where it's not prohibited or in those where the prohibitions would be lifted. The FDA ban, for example, could expire or be reversed.
KELLY MCEVERS, HOST:
It sounds like science fiction - making genetically modified babies who could pass down their new genes to future generations. But it would be acceptable for scientists to do it under some circumstances. So say the National Academy of Science and the National Academy of Medicine in a highly anticipated report that was released today. NPR health correspondent Rob Stein has the details.
ROB STEIN, BYLINE: Scientists have been allowed to tinker with human DNA for decades, but there's always been one thing that's been considered taboo. Never try to make a baby from sperm, eggs or embryos that have had their genes edited because those changes would be passed down for generations to come. Alta Charo is a bioethicist at the University of Wisconsin.
ALTA CHARO: In the past, it was never seriously considered permissible.
STEIN: For lots of reasons. Something could go wrong and accidentally create some new disease that would become a permanent part of the human genetic code or alter the course of human evolution in some unexpected ways. But recently, scientists created new ways to edit DNA.
CHARO: It made it much faster, much easier, much less expensive to do genome editing. And suddenly many different applications were suddenly possible, and it began to raise questions about whether and how to use the technology in human medical treatment.
STEIN: Including whether to try to edit the genes in human sperm, eggs or embryos to prevent babies from being born with a long list of terrible diseases. So the national academies put together a big committee to study this question. Today they released their decision. Charo co-chaired that committee.
CHARO: The committee says this. It is not ready now, but it might be safe enough to try in the future. And if certain conditions are met, it would be, from our point of view, permissible to try it.
STEIN: Those conditions include a long list of things. There's strong evidence it's safe. It could only be tried to prevent serious diseases like Huntington's, the fatal brain disorder. And there have to be a lot of safeguards to make sure nothing goes wrong.
CHARO: If they could all be met - and we mean all of them, not just some - then we conclude it would be permissible to begin clinical trials.
STEIN: And Charo stresses it could not be tried to create so-called designer babies where parents pick and choose the traits of their children to make them taller or stronger or smarter or better athletes or anything like that.
CHARO: We said, use it for serious diseases and serious conditions only - period.
STEIN: Many scientists are praising the report. Eric Lander runs the Broad Institute in Boston.
ERIC LANDER: It's important to be extraordinarily cautious on technologies that could leave a permanent mark on the human population for all generations to come. But it's important to be considering things that can help people. And I think they've been very thoughtful about how you should balance those things.
STEIN: But some say the line between preventing disease and creating genetically enhanced people will be hard to define. George Church is a prominent geneticist at Harvard.
GEORGE CHURCH: The definition of prevention of disease is very clearly broad. It could include a lot of things that some people will consider enhancement.
STEIN: And that's what makes some people very nervous.
MARCY DARNOVSKY: I don't think there's any way to keep that genie in the bottle once you've approved it for anything.
STEIN: Marcy Darnovsky is with the genetic watchdog group Genetics and Society.
DARNOVSKY: You know, these kinds of scenarios used to be science fiction, and they used to be seen as far-off hypotheticals. But actually right now, I think they're urgent social justice questions.
STEIN: Questions like whether the world's existing inequalities would only get worse.
DARNOVSKY: The perception that some children are genetically improved could lead us into a society that we would really not want to live in.
STEIN: At the moment, the federal government can't fund any research that would create genetically modified human embryos or approve any experiments to do so. Rob Stein, NPR News, Washington. Transcript provided by NPR, Copyright NPR.