Summit organisers said germline genome editing could become "acceptable" in future if rigorous criteria are met, but that there are too many scientific and technical uncertainties to permit clinical trials at this stage. He's claimed experiment was a rude awakening for scientists at the summit, and an urgent reminder that discussions about how to responsibly use a technology that could reshape the health and character of future generations might not be enough.
He said the twin girls, "Lulu" and "Nana", were born healthy after their embryos were genetically modified to make them resistant to HIV infection. Conference leaders called for an independent investigation of the claim by He Jiankui of Shenzhen, who spoke to the group Wednesday as worldwide criticism of his claim mounted.
His claim remains unproven but the incident has triggered a heated debate in the scientific community, with the organising committee of the conference, being attended by hundreds of geneticists from around the world, describing it as "deeply disturbing" and "irresponsible".
In their statement Thursday, the summit's organizers said that even if "the modifications are verified, the procedure was irresponsible and failed to conform with worldwide norms." Dr.
Dr. He told his colleagues he conducted his research in secret.
The revelation shone a light on a new technology called CRISPR-Cas9, a tool that allows researchers to replace faulty genes with new ones, but research is not fully clear on its effect on humans.
More than 100 scientists, most in China, said in an open letter on Tuesday the use of CRISPR-Cas9 technology to edit the genes of human embryos was risky and unjustified.
Another couple was pregnant at present he said. One of the couples dropped out while these twins were born.
Since then several scientists have reviewed the material that He Jiankui provided to the AP, tests so far are suggested to be insufficient to say editing worked to rule out harm, noting evidence of editing being incomplete, and at least one twin appears to be a patchwork of cells with various changes, nearly as if not editing at all.
Gene-editing technology had been used to immunise them from HIV, he claimed. It is not clear whether the participants fully understood goal and potential risks and benefits.
"They need this protection since a vaccine is not available", He said. Staff at other hospitals were kept in the dark about the nature of his work to keep some of the participants information from being disclosed other than the fact that the samples might contain HIV.
There is no independent confirmation of He's claim, and he has not yet published in any scientific journal where it would be vetted by experts.
Xu called the team's actions illegal and unacceptable and said an investigation had been ordered.
In China, where scientists have forged ahead with astonishing speed, regulations are still catching up.
After news of Mr He's work came to light earlier this week, Chinese scientists were quick to denounce it, as was his institution, the Southern University of Science and Technology in Shenzhen.
Hours after the summit closed Thursday, a high-ranking Chinese official told a state broadcaster that He's project has been suspended amid a government investigation.