CRISPR, first described in 2012, gives scientists the most precise and effective way to edit the human genome by snipping out offending mutations or genes and either allowing the genome to fix itself or providing researchers with the ability to insert new genetic material to correct disease genes.
The technique carries the risk that altered DNA will warp other genes - potentially risky mutations that may then be passed down to future generations. But studies suggest that controlling CRISPR in human cells remains a challenge; in some cases CRISPR may cut unintended parts of the genome. 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's experiment altered the genomes of embryos produced through IVF; their genetic changes will therefore be passed on to any future generations.
Chinese Vice Minister of Science and Technology Xu Nanping told state broadcaster CCTV that his ministry is strongly opposed to the efforts that reportedly produced twin girls born earlier this month. Harmonicare Women's and Children's Hospital, where He said he received ethical approval for his research, denied they had given him the go-ahead and filed a report with police.
The reports fall in the grey area between attempts to cure diseases, and the dreaded "designer baby" scenario, where humans could be modified for benefits unrelated to health (potentially expanding to include intelligence, aesthetics and more).
The Shenzhen university distanced itself from He in a statement Monday that said the researcher had been on unpaid leave from February 1, 2018 and was not expected to return until January 2021. The objective of the edit was to remove the CCR5 gene, which helps enable many forms of the HIV virus to infect cells. "All medical advances, gene editing or otherwise and particularly those that impact vulnerable populations, should be cautiously and thoughtfully tested, discussed openly with patients, physicians, scientists, and other community members, and implemented in an equitable way".
Dr He Jiankui revealed the birth of the baby twin girls ahead of a major genome editing conference in Hong Kong.
He's experiment "crossed the line of morality and ethics adhered to by the academic community and was shocking and unacceptable", Xu said.
He received his PhD at Rice University in Houston, Texas, and worked as a postdoctoral research fellow in Stephen Quake lab at Stanford University according to the site.
But in people, gene editing still is highly experimental. "The study has been submitted to a scientific journal for review", he added.
This is not the first time Chinese researchers have experimented with human embryo technology.
In a pre-recorded video on the conference's website, biologist and chair of the global summit David Baltimore 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".
Doctors and ethicists have long feared the day when genetic engineering would begin to be used in humans and now it's claimed those fears have become reality.
"If this was done to avoid HIV infection, there are alternative ways to prevent infection that are already effective", Doudna says, such as "washing" the sperm of infected sperm donors to eliminate HIV. However, eradicating diseases at the source is certainly a noble mission and I for one, would love to see He's research propagated and taken up by others.