A group of leading scientists has declared it is too soon to try making permanent changes to DNA that can be inherited by future generations, as a Chinese researcher claims to have done.
However, despite being a heavy investor in gene-editing, more than 120 Chinese scientists have condemned He Jiankui's work as it has dealt a massive blow to their biomedical research reputation and wrote, "It's extremely unfair to Chinese scientists who are diligent, innovative and defending the bottom line of scientific ethics... directly experimenting on human is nothing but insane... as soon as a living human is produced, no one could predict what kind of impact it will bring, as the modified inheritable substance will inevitably blend into human genome pool".
Most scientists in the field, however, have chosen not to jump the gun and begin performing the work on human embryos with the intention of producing modified babies.
CRISPR is a tool that can precisely cut-and-paste genes, allowing a part of DNA to be removed and replaced.
The Chinese researcher said he practiced editing mice, monkey and human embryos in the lab for several years and has applied for patents on his methods.
Shortly after his talk, He canceled a planned appearance in a Thursday session on embryo gene editing, according to the Royal Society, one of the conference organizers.
"The clinical use of genome editing in the germline of humans is premature given that we don't fully understand the technology and the impact of that kind of application, and it has a potentially very longstanding effect on a person's life and their future kids", says Jennifer Doudna, who helped develop the CRISPR-Cas9 gene editing technique He used. When the eggs and sperm were combined, the scientists also added a CRISPR protein that had been "told" to alter the CCR5 gene.
When the embryos were 3 to 5 days old, a few cells were removed and checked for editing. Doudna, a professor at the University of California, Berkeley, says she hopes CRISPR will someday be used to edit bad diseases out of the human genome.More news: Tweets document damage after 7.0 quake rocks Alaska, sparking tsunami warning
One of many areas of confusion about Dr.
Since then several scientists have reviewed the material that He Jiankui provided to the AP, tests so far are suggested to be insufficient to say editing worked to rule out harm, noting evidence of editing being incomplete, and at least one twin appears to be a patchwork of cells with various changes, nearly as if not editing at all.
He also said that "another potential pregnancy" of a gene-edited embryo was in its early stages.
"This experiment exposes healthy normal children to risks of gene editing for no real necessary benefit". It is not clear whether the participants fully understood goal and potential risks and benefits. An expert in vaccine development, He said his aim is to rid the world of HIV, the virus that causes AIDS. The school denounced his research for violating "academic ethics and codes of conduct", and the Chinese government is urging local authorities to launch an investigation into He's work.
Some staff at some of the other hospitals were kept in the dark about the nature of the research, which He and Deem said was done to keep some participants' HIV infection from being disclosed.
He's experiment has not been independently verified.
China's National Health Commission has ordered an investigation into Dr He's experiment. If the births are confirmed the case will be handled in accordance to relevant laws and regulations, it is not clear whether there could be possible criminal charges.