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Hundreds of scientists, bioethicists and patients are coming together in London for the Third International Summit on Human Genome Editing. They'll debate and maybe make recommendations about new gene-editing technologies. NPR health correspondent Rob Stein has the story.
ROB STEIN, BYLINE: The last time the pros and cons of gene editing came up for formal debate, a Chinese scientist named He Jiankui dropped a bombshell. He had created the world's first genetically modified humans.
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HE JIANKUI: Two beautiful little Chinese girl named Lulu and Nana came crying into the world as healthy as any other babies a few weeks ago.
STEIN: He Jiankui's actions were condemned as irresponsible and unethical. But in the five years since that stunning announcement in Hong Kong, scientists have quietly continued to hone their gene-editing skills.
ROBIN LOVELL-BADGE: A lot has happened over the last five years. It's been a busy period.
STEIN: Robin Lovell-Badge from the Francis Crick Institute in London led the committee convening the new summit.
LOVELL-BADGE: The number of clinical trials involving genome editing has gone up enormously in those last five years. So we're having a lot more experience of how to do it and how it might work. Various techniques have been developed and improved substantially. So, you know, there's a lot of new stuff.
STEIN: Doctors have made dramatic advances using the gene-editing technique He Jiankui used, known as CRISPR, to treat many diseases. Scientists have learned more about the risks of gene editing while also developing more sophisticated techniques that could be safer and more precise. Jennifer Doudna at the University of California, Berkeley, is one of CRISPR's pioneers.
JENNIFER DOUDNA: We're at an exciting moment for sure with genome editing. At the same time, we certainly have challenges.
STEIN: One big challenge remains whether scientists should ever again try to make gene-edited babies by modifying the DNA in human sperm, eggs or embryos. That could help families that have been plagued by devastating genetic disorders. But the fear is a mistake could create new genetic diseases that could then be passed down for generations, becoming a permanent part of the human gene pool and about opening a slippery slope to designer babies. Marcy Darnovsky heads the Center for Genetics and Society in San Francisco.
MARCY DARNOVSKY: If we were to allow parents to genetically modify their children, we would be creating new groups of people who were different from each other biologically, and some would have been modified in ways that are supposed to enhance them. And they would be, unfortunately, I think, considered an enhanced race, a better group of people. And I think it could really just supercharge the kinds of inequities that we already have in our world.
STEIN: But some say the debate over the last five years has shifted from whether the taboo on inheritable genetic modification should ever be breached to what technical hurdles need to be overcome to do it safely. And doctors are asking which diseases they should try to eradicate from families. The subject of genetically modifying embryos, sperm and eggs is the focus of only one of three days of the first summit since the CRISPR babies. Sheila Jasanof is at Harvard's Kennedy School of Government.
SHEILA JASANOF: This is quite an ironic outcome. I mean, so instead of rejuvenating the calls to say we should be much more careful, it was as if the whole scientific community heaved a kind of sigh of relief and said, well, look, of course there are limits. This guy has transgressed the limits. He's clearly outside the limits. And therefore, everything else is now open for grabs. And therefore, the problem before us now is to make sure that we lay out the guidelines and the rules.
STEIN: That way of talking about making genetic modifications that can be inherited, critics say, could encourage others to rush ahead prematurely and again try to make more gene-edited babies. Even now, He Jiankui appears to be trying to rehabilitate himself after serving a three-year prison sentence. He set up a new lab in Beijing, is promising to develop new gene therapies for diseases like muscular dystrophy. He declined requests from NPR for an interview, but here's a bit from one of his recent lectures he posted online.
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HE: (Non-English language spoken).
STEIN: He's not talking about creating more gene-edited babies. Still, his activities are raising alarm. The only public regret he's offered is that he moved too fast. Here's Robin Lovell-Badge again from the Francis Crick Institute.
LOVELL-BADGE: I'm concerned. Do you really want someone like this who is - has already shown that he can do science in a bad way, deal with patients in a bad way? Really - I'm not speaking very clearly 'cause I - obviously you can tell I'm a little angry about this. I'm surprised that he's being allowed to practice science again.
STEIN: But Badge and other organizers of the summit dispute criticisms that scientists are assuming gene-edited babies are inevitable and that the summit is shortchanging a debate about the ethical and societal land mines. The summit's dedicating the last day of the meeting to genetic modifications that can be passed down through generations, featuring scientists as well as a broad array of watchdog groups, patient advocates, bioethicists, sociologists and others. The summit's focusing the first two-thirds on gene editing to treat diseases in people already born because that's already a reality and raising its own concerns, they say. Francois Baylis is a bioethicist at Dalhousie University in Canada who helped plan the summit.
FRANCOIS BAYLIS: We're not moving away from the conversation around heritable human genome editing, but we are trying to shift some of that focus. And I think really important in this context is the issue of cost, because we have been seeing gene therapies come onto the market with million-dollar price tags. That's not going to be available to the average person.
STEIN: Especially in poor countries, where some of the new genetic therapies are needed most. So it's clear that the London gene-editing summit has a lot of tough issues to grapple with.
Rob Stein, NPR News.
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