A Chinese scientist's claim that he created the world's first genetically-edited babies has shone a spotlight on what critics say are lax regulatory controls and ethical standards behind a series of headline-grabbing biomedical breakthroughs in China.
More than 100 scientists, mostly in China, said in an open letter on Tuesday the use of CRISPR-Cas9 technology to edit the genes of human embryos was unsafe and unjustified. 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.
Italian surgeon Sergio Canavero sparked controversy past year when he claimed to have conducted the world's first head transplant on a corpse at a Chinese hospital, the state-run Global Times reported at the time, though other scientists have called his claims overblown.
But He took to the stage on Wednesday to justify his work, and was bombarded with questions as he told the audience that the parents were aware of the potential dangers when they signed up. He said he would monitor the two newborns for the next 18 years and hoped they would support continued monitoring thereafter. He also said that the seven couples, each with one HIV-positive partner, who provided eggs and sperm for the experiment were thoroughly informed about the scientific process, including the risks involved.
It's "unconscionable.an experiment on human beings that is not morally or ethically defensible", Musunuru said.
He did not name the journal and said his university was unaware of his study.
I think there's been a failure of self-regulation by the scientific community because of a lack of transparency.He meticulously orchestrated the announcement on Sunday - two days before the start of the summit - of his claim that the girls, created from genome-edited embryos, had been born a few weeks ago.
Genetic editing, the subject of Kazuo Ishiguro's 2005 dystopian novel Never Let Me Go, has seized the imagination - and fear - of humans for decades.
But scientists were left scrambling to understand what exactly He and his colleagues had done - and whether their gene-editing succeeded.
Gene editing may be morally legitimate, DiCamillo said, when used for "a directly therapeutic goal for a particular patient in question and if we're sure we're going to limit whatever changes to this person".
He Jiankui (JEE-ahn-qway) of Shenzhen detailed the work that he said led to the births earlier this month of twin girls whose DNA he altered when they were conceived. They also said that eliminating the CCR5 gene - the crux of He's experiment - can not completely rule out the possibility of the babies contracting HIV.
The Chinese Society for Cell Biology in a statement on Tuesday strongly condemned any application of gene editing on human embryos for reproductive purposes and said that it was against the law and medical ethics of China. Expanding on his motivations in a YouTube video, He spoke about discrimination that HIV-positive people still face in China and many developing countries.
Even one of the inventors of CRISPR, Feng Zhang, told the Massachusetts Institute of Technology it was not worth the risk to start editing embryos' genes right now.
"I call (the guide RNA) the ZIP code director: It recognizes a specific region of DNA, so you can direct the Cas9 protein - which cuts DNA - to a specific point in the genome", she said.
The Associated Press reported on the claims of a Chinese researcher, who announced that twin girls were born with "a powerful new tool capable of rewriting the very blueprint of life". "I personally don't think it was medically necessary".
But genome editing could also more controversially used for genetic enhancements, such as ensuring children have a particular desirable characteristic such as a certain eye colour.