A Chinese scientist who claims to have created the world's first genetically edited babies has defended his work.
The scientist was speaking at a genome summit in Hong Kong on Wednesday. When questioned about the controversy over what he claims are the world's first genetically edited children said he was proud of his work and revealed that another volunteer is pregnant as part of the research.
He Jiankui, an associate professor at Southern University of Science and Technology in Shenzhen, China, addressed a packed hall of around 700 people attending the Human Genome Editing Summit at the University of Hong Kong.
In a video posted on Sunday, university professor He Jiankui announced the birth of twin girls whose DNA had been edited to prevent HIV infection. He said the twins’ DNA was modified using CRISPR-Cas9, a technique that allows scientists to remove and replace a strand with pinpoint precision. His work has not been independently verified.
"For this case, I feel proud. I feel proudest," He said, when challenged by several peers at the conference.
"This study has been submitted to a scientific journal for review," He said. He did not name the journal and said his university was unaware of his study.
However, he said the trial has now been paused in the wake of the outcry.
"I must apologise this result was leaked unexpectedly," said He. "The clinical trial was paused due to the current situation," he added.
He, who said his work was self-funded, shrugged off concerns that the research was conducted in secrecy, explaining that he had engaged the scientific community over the past three years.
In videos posted online this week, He said he used a gene-editing technology known as CRISPR-Cas9 to alter the embryonic genes of twin girls born this month.
He said gene editing would help protect the girls from infection with HIV, the virus that causes AIDS.
But scientists and the Chinese government have denounced the work that He said he carried out, and a hospital linked to his research suggested its ethical approval had been forged.
A total of eight volunteer couples – HIV-positive fathers and HIV-negative mothers – had signed up to the trial, with one dropping out before it was halted.
Fellow Chinese scientists were appalled by He’s work. A joint statement issued by more than 120 Chinese scientists condemned it as “madness” and called on authorities to enact laws on this kind of research.
“The Pandora’s Box has been opened, but we may still have a chance to close it before it is irreparable,” the statement said, criticising the influence of He’s work on other Chinese scientists. “It is extremely unfair to Chinese scientist who are diligent, innovative and defending the bottom line of scientific ethics.”
Amid the outcry, research institutions connected to He have distanced themselves from the scientist. “This research work was carried out by Professor He Jiankui outside of the school,” the Southern University of Science and Technology in Shenzhen, where He worked, said on Monday. It called his research a “serious violation of academic ethics and norms”.
A hospital in Shenzhen where He said he received approval from an ethics board to conduct his work denied any link to He. The hospital, Shenzhen Harmonicare Women’s and Children’s Hospital, said it has lodged a report with the police.
The conference moderator, Robin Lovell-Badge, said the summit organisers were unaware of the story until it broke this week.
A leader of the international conference on gene editing said He's work showed a failure of self-regulation among scientists.
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