"The girls are safe and healthy as any other babies", He said without offering any evidence of his work, which has not been independently verified or published.
The university's biology academic committee said He's work "seriously violates academic ethics and academic norms".
"It's obscene, it's hearsay, but the two babies have been genetically altered differently", Brown told 10 daily.
If He's claims are accurate, Annas wrote, then the academic violated "a growing medical-scientific consensus that gene editing not be used on human embryos to create a baby until much more is known about its safety (especially "off target" effects), how to obtain informed consent, and how to monitor any resulting children (and their children) for at least 3 generations (indeed, the Hong Kong conference is the second global one on the science and ethics of Human Genome Editing, designed especially to create an worldwide consensus)".
Doudna also cited the global consensus reached in 2015.
The claims by He sparked immediate widespread criticism from attendees at the summit and elsewhere.
"Despite the fact that this is the most significant experiment in the history of human genetics, it is operating with a laissez-faire, let each nation decide approach", said Arthur Caplan, a bioethicist at the New York University School of Medicine. Doudna helped discover CRISPR and organize the summit. Also: "We will publish our full data soon". "We know very little about the long-term effects, and most people would agree that experimentation on humans for an avoidable condition just to improve our knowledge is morally and ethically unacceptable".
If parents were given the choice of implanting either edited or unedited embryos, and if they were adequately informed about the risks of using CRISPR technology, then that is where decisions about the ethics of using this technology should properly rest. She doesn't think that is the case in this situation.
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On Twitter he wrote that "the regime and its allies are using this as an excuse to launch a military operation in north Syria". Pictures and footage on SANA showed medical workers carrying patients on stretchers and helping them with oxygen masks.
The process is being promoted as a means to eliminate the threat of HIV. The gene modification was done with the help of CRISPR, a gene-editing tool that is cheap and easy to use. Scientists have long searched for ways to block this pathway to protect people from HIV.
"No gene was changed except the one to prevent HIV infection", He says.
They also noted evidence that the editing was incomplete and that at least one twin appears to be a patchwork of cells with various changes.
Jennifer Doudna, one of the pioneers of genome editing from the University of California, Berkeley, said that the experiment appeared to be a "clear break" from the cautious and transparent approach recommended by worldwide leaders. Many scientists working in genetics say they believe such experimentation is risky.
CRISPR-Cas9 is a technology that allows scientists to essentially cut-and-paste DNA, raising hope of genetic fixes for disease.
A Chinese scientist claims he successfully created the world's first genetically-edited babies. The tool has been used recently to treat deadly diseases in adults, but not in editing sperm, eggs, or embryos.
"Of the group infected with HIV, many have special conditions such as inability to conceive naturally, but the reality is that they can not have babies through IVF in hospitals", he said.
Crispr has made it possible to edit tiny segments of a genome, and to perform that editing much more easily than ever before.
"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".
But making changes in human DNA that could be passed down for generations has always been considered off-limits.