The conference was rocked by the Chinese researcher's claim to have helped make the world's first gene-edited babies.
Media reports triggered Shenzhen's Southern University of Science and Technology, where He is now on unpaid leave, to release a statement Monday explaining that the organisation was "deeply shocked" and is trying to establish communications with He to clarify the extent of his research.
The issue of editing human DNA is extremely controversial, and only allowed in the USA in laboratory research - although United States scientists said a year ago that they had successfully edited the genetic code of piglets to remove dormant viral infections.
When He's claims became public, the university issued a statement saying his work had "seriously violated academic ethics and standards".
CRISPR is a molecular tool that allows scientists to edit sections of DNA.
The researcher said he used the gene-editing tool CRISPR to alter a gene named CCR5 in embryos for seven couples during their fertility treatments; one pregnancy resulted. Scientists discovered this natural mutation in the late 20th century, when they realized those with two copies - about 10 percent of Europeans - were also protected from HIV.
He said: "We have never done anything that will change the genes of the human race, and we have never done anything that will have effects that will go on through the generations".
Scientist He Jiankui of Shenzhen says he said he has altered DNA in human embryos, and that healthy twin girls are now at home with their parents.
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"This is far too premature", said Dr. Eric Topol of California's Scripps Research Translational Institute said it was "far too premature" to be "dealing with the operating instructions of a human being". He's fairly convinced that the experiment was real, though the results have yet to be published in the open scientific literature. He sought to disable a gene called CCR5 that forms a protein doorway that allows HIV, the virus that causes AIDS, to enter a cell.
The main objection to He's supposed gene-editing of Nana and Lulu boils down to one simple fact: messing with a human's genes is incredibly unsafe and inhumane, mostly because we don't fully understand how it works. He added that a further six couples are participating in the gene editing program, though their babies have not yet been born. He is expected to present his findings on Wednesday at the Second International Summit on Human Genome Editing in Hong Kong. An American scientist, Michael Deem of Rice University, also worked on the project.
He's experiment "crossed the line of morality and ethics adhered to by the academic community and was shocking and unacceptable", Xu said. Both the hospital and the university denied that the gene editing procedure had been conducted in their facilities.
Kiran Musunuru is a University of Pennsylvania gene editing expert and editor of a genetics journal.
"We've been talking about genetic engineering of embryos for a while... what is a bit more revolutionary is that these children were allegedly engineered to provide resistance to a disease".
This is not the first time Chinese researchers have experimented with human embryo technology.
At around 3 to 5 days old, a few cells were taken from the embryo and checked if it was possible to edit them.