While He offered his apologies for the controversy his experiment has generated, the scientist defended his work, expressing pride in what it accomplished.
CRISPR is a tool that can precisely cut-and-paste genes, allowing a part of DNA to be removed and replaced.
Scientists do not know whether there were any unintended edits to other genes, Musunuru says.
He Jiankui states that he practiced gene editing in mice, monkey, and human embryos in lab trials for several years and has applied for patents in his methods.
He Jiankui, an associate professor at Southern University of Science and Technology in Shenzhen, addressed about 700 people attending the Human Genome Editing Summit at the University of Hong Kong on Wednesday.
It's important to note here the science has not been posted on a preprint server or published in a peer-reviewed journal - the usual standard applied to confirm new research is valid and ethically sound. Questions remain about the way he proceeded, giving official notice of his work long after he said he started it on Nov 8 on a Chinese registry of clinical trials.
In China the prevalence of HIV infection is high, and access to health care a serious public health concern. The couples had received hours of counselling before the procedure, with He promising that he would improve their children as well as making them resistant to HIV. Two babies, a pair of twin girls, have already been born and more are allegedly on the way. They modified the DNA of the embryos, verified the molecular scissors were truly on target and implanted edited embryos in the mother's body. One of the couples dropped out while these twins were born.
We have little to no details on how this was performed and we must take these reports with a lot of caution.
The price of oil has updated the annual minimum
Russian Federation is the second biggest oil exporter in the world, making its economy vastly dependent on the global oil market. The supply and demand fundamentals remain bearish, but the early price action suggests the technical picture may be improving.
Gene editing could potentially help avoid heritable diseases by deleting or changing troublesome coding in embryos.
Editing DNA is highly controversial and is only allowed in the USA and United Kingdom in laboratory research.
With so many genetics researchers in one place this week, opinions on He's work have come fast but vary little. The first modification of human embryos was reported by another Chinese team in May 2015.
This led to the the Chinese Academy of Sciences (CAS), the Royal Society (RS), and the U.S. National Academy of Sciences (NAS) and U.S. National Academy of Medicine (NAM) coming together to organise an International Summit on Human Gene Editing in December 2015 in Washington, DC.
The global scientific community decided back in 2015, when CRISPR editing of human genes first became feasible, that gene editing should begin by addressing hereditary diseases, such as sickle cell anemia and cystic fibrosis. Scientists from across the globe lambasted He's experiment.
Based on the information now available, it is hard not to consider this latest experiment as anything but an attempt to win a "race" and grab attention.
Southern University of Science and Technology distanced itself from He, saying he had been on unpaid leave since February and had "seriously violated academic ethics".
Collins said the NIH was taking preliminary steps to investigate a Rice University researcher who served as He's graduate advisor when He pursued graduate study at the Houston university and who has acknowledged participating in his protege's research.