Conference moderator Robin Lovell-Badge said He’s trial was a “backward step” for the science industry, but described the babies’ birth as “momentous” nonetheless.
“This is an example of an approach that was not sufficiently careful and cautious and proportionate,” he said.
“Clearly however … it is a momentous point in history.”
Summit chair David Baltimore, a Nobel laureate, said there had been “a failure of self-regulation by the scientific community”.
Antonio Regalado, senior editor for biomedicine for MIT Technology Review — the publication which first highlighted the trial on Sunday — said He’s talk was “ethically a half-baked mess”.
He, who was educated at Stanford University, said the twins’ DNA was modified using CRISPR, a technique which allows scientists to remove and replace a strand with pinpoint precision.
But the co-inventor of CRISPR condemned He’s trial as dangerous and unnecessary.
“My concern is that this experiment really shouldn’t have happened,” Feng Zhang told reporters at the conference. “What he has done was not transparent … does not represent science.”