China's science ministry on Thursday ordered that anyone conducting research in gene editing halt their activities.
The order came as organizers of a biomedical conference where a Chinese scientist defended his claim that he has created the world's first genetically-edited babies denounced his work as irresponsible.
The leaders of the Second International Summit on Human Genome Editing issued a statement Thursday on the last day of their conference in Hong Kong criticizing He Jiankui's claim as "deeply disturbing."
Dr. He spoke to the summit on Wednesday about his work in claiming to have used a gene-editing technology dubbed CRISPR to alter the DNA of twin girls born to an HIV-positive father to prevent them from contracting the virus that causes AIDS. The researcher first made the claim in an online video posted Monday.
Dr. He told his colleagues he conducted his research in secret. His work has not been independently verified, and Dr. He has not submitted his report to any scientific journals where it could be examined by experts.
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 international norms." Dr. He was supposed to speak before the summit again Thursday, but canceled his appearance.
He's claims has set off a firestorm of skepticism and criticism. The Southern University of Science and Technology, the university in the southern Chinese city in Shenzhen that employs him, says he has been on unpaid leave since February. The school denounced his research for violating "academic ethics and codes of conduct," and the Chinese government is urging local authorities to launch an investigation into He's work.
Genetic editing has the potential to remove inherited diseases from the gene pool, but scientists and ethicists worry it could be used to create so-called "designer babies." They also worry any genetic changes could lead to other genes being altered in unpredictable ways.