Science Summit Denounces Gene-Edited Babies Claim, But Rejects Moratorium

Nov 29, 2018
Originally published on November 29, 2018 11:27 pm

A Chinese scientist's claims that he created the world's first gene-edited babies is a "deeply disturbing" and "irresponsible" violation of international scientific norms, according to a formal conclusion issued Thursday by organizers of the Second International Summit on Human Genome Editing in Hong Kong.

But the summit rejected calls for a blanket moratorium on such research, saying that the work could eventually lead to new ways to prevent a long list of serious genetic diseases.

"Making changes in the DNA of embryos could allow parents carrying disease-causing mutation have healthy genetically related children," said David Baltimore, a Nobel-prize winning U.S. biologist who chaired the summit.

The summit was jolted by scientist He Jiankui's surprise and unverified claims earlier this week that he had edited the genes of twin girls who were born last month.

He, of the Southern University of Science and Technology in Shenzhen, China, claims he modified the embryos of the twins with the gene-editing technique CRISPR so that they would be immune to the AIDS virus. His claims remain unproven.

Nevertheless, hundreds of scientists from dozens of countries were engrossed by his claims as they gathered for the three-day summit, which was organized by the Academy of Sciences of Hong Kong, the Royal Society of London, the U.S. National Academy of Sciences and the U.S. National Academy of Medicine.

The goal was to reach a global scientific consensus on how scientists might some day ethically use powerful new gene-editing techniques such as CRISPR to edit the human genetic blueprint.

A question of ethics

In the summit's closing statement released early Thursday, the organizers called for an investigation to verify or refute He's claims. But regardless of whether it is true, the organizers said the researcher's experiment was premature, deeply flawed and unethical.

"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," said Baltimore.

Much more research is needed before anyone tries to prevent diseases by editing human embryos, the organizers concluded.

"Making changes in the DNA of embryos ... could allow parents who carry disease-causing mutations to have healthy, genetically related children," Baltimore said. "However, heritable genome editing of ... embryos ... poses risks that remain difficult to evaluate."

But enough scientific advances have been made since the last summit in 2015 to begin plotting a course for how that could happen some day, according to the statement.

"Progress over the last three years and the discussions at the current summit, ... suggest that it is time to define a rigorous, responsible ... pathway toward such trials," said Baltimore, a Nobel-prize winning U.S. biologist.

In doing this, the organizers rejected calls for a moratorium on such research.

Baltimore said "draconian bans would be antithetical to the goals of science," and unnecessarily hinder the advancement of science.

R. Alta Charo, a University of Wisconsin bioethicist who helped organize the summit, argued that just because one scientist violated scientific norms, doesn't necessarily mean the scientific system is flawed.

"I think the failure was his, not the failure of the scientific community," Charo said. "You can't expect to have perfection. What you can try to do is minimize these incidents with the constant effort of conversation and oversight and ultimately enforcement measures that will discourage rogue behavior that goes outside international norms."

Concerns and possible benefits

Making changes to the DNA in human embryos has long been considered taboo because of safety concerns and fears it could lead to "designer babies" — children whose traits are picked to make supposedly genetically superior people.

But many scientists have now become convinced that it may be ethical someday to edit human embryos to prevent genetic disorders, such as Huntington's disease, cystic fibrosis, muscular dystrophy and hemophilia. And several scientists have already edited human embryos in their labs to try to determine the safety and effectiveness of the procedure.

Most scientist and bioethicists agree that it is far too early to try to make babies from edited human embryos — primarily because safety protocols for the technique remain unclear.

DNA editing may inadvertently cause genetic mutations that could cause health problems for any babies created this way and cause new health problems that would then be passed down for generations.

Some oppose all efforts to create genetically modified babies, saying it will be extremely difficult to draw a clear line between medical uses and attempts to create genetically enhanced individuals. And that could lead to a world of genetic haves and have-nots.

Varied regulations

While gene-editing experiments on human embryos is prohibited in many countries, it has not been barred in many others. And scientist have long relied on self-regulation to prevent new technologies from being abused.

The summit statement came amid a growing call for governments around the world to impose enforceable moratoriums on any future experiments. While such experiments are prohibited in some countries, previous scientific policing has largely relied on scientists to follow guidelines.

As the summit opened, Feng Zhang, an MIT scientist who helped develop CRISPR, immediately called for a moratorium on such experiments.

"Given the current early state of genome editing technology, I'm in favor of a moratorium on implantation of edited embryos ... until we have come up with a thoughtful set of safety requirements first," Zhang wrote in a statement.

But after the summit, Zhang said he agreed with the outcome.

"Rather than focusing on criticizing what has happened, we should learn the lessons that it has taught us," Feng wrote in an email. "There is a lot of potential for using gene editing to alleviate disease suffering, and providing a productive path forward is the best way to ensure that patient's hopes will get realized."

As the last day of the summit was getting underway, more than 100 activists, bioethicists, scientists and other released a joint statement calling for the summit to call on governments and the United Nations to adopt moratoriums.

"If the organizers of this week's summit in Hong Kong wish to demonstrate that science is not out of control, and is worthy of public trust, now is the time for them and the rest of the international scientific community to act," the statement said.

It noted that when He defended his experiment at the summit, he justified his experiment in part on a 2017 report from the National Academies of Sciences. That report concluded that clinical trials "might be permitted" after laboratory studies show it would be safe and then only for "compelling medical reasons in the absence of reasonable alternatives."

That sentiment was echoed by the Berkeley, Calif., based Center for Genetics and Society, which accused the summit organizers of "complicity" in He's rogue research, saying the recommendations of the National Academies and the Nuttfield Council of Bioethics had been interpreted as a "green light" by He.

In their closing statement, the summit organizers "all but said outright that nothing will get in their way: not laws in dozens of countries or an international treaty, not widespread public and civil society opposition, not deep concern among their own scientific community, and not a grandstanding researcher," CGS said in a statement.

David King of Human Genetics Alert, brought up the specter of "[the] horrifying history of eugenics in the 20th century," and warned of the "disastrous consequences of going down this path."

"It should act immediately to prohibit such experiments, and ensure that He Jiankui is prosecuted as a warning to others," King said in a statement.

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An international summit on gene editing has formally condemned the claims of a Chinese scientist who says he's created the world's first gene-edited babies. But as NPR health correspondent Rob Stein reports, the summit rejected calls for a global moratorium on the creation of more gene-edited children.

ROB STEIN, BYLINE: The hundreds of scientists who gathered this week in Hong Kong were shocked by the Chinese scientist's claim that he had created genetically edited twin girls. He says he edited their DNA when they were embryos in his lab to protect them from the AIDS virus.


DAVID BALTIMORE: At this summit, we heard an unexpected and deeply disturbing claim that human embryos had been edited and implanted, resulting in a pregnancy and the birth of twins.

STEIN: That's David Baltimore, a Nobel Prize-winning biologist who chaired the summit.


BALTIMORE: The procedure was irresponsible and failed to conform with international norms.

STEIN: For lots of reasons - it was done secretly and way before most scientists think it's safe to try this sort of thing. And it may only have partially worked if at all. The Chinese scientist says only one of the twins had both copies of her targeted gene called CCR5 edited, and so only one of the girls could actually be protected from HIV. And the scientist, He Jiankui, made another startling claim during questioning at the summit yesterday.


UNIDENTIFIED PERSON: Are there any current pregnancies with embryos that have been genome-edited as part of your clinical trials?

HE JIANKUI: There is another one, but need time to monitor. There's another potential pregnancy.

STEIN: But it's unclear what happened to it. The summit organizers are calling for a formal investigation to try to find out whether any of the scientist's claims are true. But they stress they hope the Chinese experiment does not set back work by responsible scientists and reject calls for a worldwide moratorium on any efforts to ever create gene-edited babies. Here's David Baltimore again.


BALTIMORE: There have already been statements made that are very worrisome because they suggest draconian bans, which is really antithetical to the goals of science.

STEIN: If it's someday proven to be safe and ethical, Baltimore says genetically edited human embryos could prevent a long list of terrible genetic diseases. Critics, however, denounce the summit's decision to endorse continued research, saying it just opens the door for more unethical experiments by more rogue scientists. Marcy Darnovsky is with the Center for Genetics and Society.

MARCY DARNOVSKY: Once you open this Pandora's box a crack, all the bad genies, you know, fly out. And they're really hard to get back in.

STEIN: There's nothing stopping other scientists from editing human embryos for other reasons, Darnovsky says, including to create designer babies. Rob Stein, NPR News. Transcript provided by NPR, Copyright NPR.