A group of Chinese scientists have revealed that they genetically modified human embryos to make them HIV-resistant, a controversial move that may reignite an ethics debate but otherwise shows China's ambition to take the lead in gene-editing research.
Researchers at Guangzhou Medical University in China have altered an immune gene in human embryos using a technique known as CRISPR-Cas9, according to a paper published in the Journal of Assisted Reproduction and Genetics on April 6.
"We used flawed embryos that were not viable for fertility treatment," Fan Yong, the paper's lead author, said in a statement sent to the Global Times Tuesday.
Fan said the research had been approved by the ethics committee of the Third Affiliated Hospital of Guangzhou Medical University, adding that all the embryos were destroyed after three days.
The result of the experiment was only partially successful as only four of the 26 embryos were successfully modified and some embryos showed unplanned mutations.
The team's major progress is the use of CRISPR to successfully introduce a precise genetic modification, George Daley, a US stem-cell biologist, was quoted by the journal Nature as saying on Friday.
This is the second Chinese team to have sparked global deliberation about the ethics of such experiments.
In a research paper published in April 2015, Chinese scientists described how they were able to manipulate the genomes of human embryos for the first time. Huang Junjiu, a gene-function researcher at Zhongshan University in Guangzhou, described, along with his team, how they used the CRISPR-Cas9 technique to modify the genomes of embryos obtained from a fertility clinic, AFP reported.
"Generally speaking, the technology can be applied to treat all diseases caused by inherited variation, including cancers," Han Bin, director of the National Center for Gene Research at the Chinese Academy of Sciences (CAS), told the Global Times.
Slippery slope
Critics worry that altering genes this way is a slippery slope that ultimately results in "designer babies."
"This is the first step on a path that scientists have carefully mapped out toward the legalization of [genetically modified] babies," David King, of anti-gene manipulation group Human Genetics Alert, was quoted by the Associated Press (AP) as saying in February.
However, some scientists argued that the technique applied to non-viable human embryos can be defended ethically.
"Such research paves the way to treatment … More importantly, the immature technique is too early for clinical uses … The abnormal embryos in the experiment are unable to grow," Qiu Renzong, the first Chinese laureate for the Avicenna Prize for Ethics in Science, told China Science Daily in 2015.
Fan also argued that "regardless of criticism, which is not authoritative … we have to stick to the path, obtain independent intellectual property rights and a say [in international academia]."
Similar to artificial intelligence, gene editing in human embryos faces both opportunities and risks, said Fan. "Whether Chinese scientists do the research or not will not stop the technique from advancing. But it is the pioneers that will make the rules in this field," he said.
"Intensive basic and preclinical research is clearly needed and should proceed, subject to appropriate legal and ethical rules and oversight," according to a statement jointly issued by CAS, the US National Academy of Sciences and the Royal Society on the International Summit on Human Gene Editing in December 2015.
Fan noted that their and Huang's research has given Chinese scientists a head start in the fierce international competition.
Instead of following other countries' stance over those sensitive issues in science, the Chinese government should carefully formulate their own standards and regulations, Han said.
Supervision needed
Laws and guidelines vary widely across the world about what type of research is allowed on embryos. In the US, research on human embryos cannot be funded by the National Institutes of Health, AP reported.
The UK's fertility regulator, the Human Fertilization and Embryology Authority, granted its first license for the genetic modification of human embryos in February as part of research into infertility and why miscarriages happen.
"We advocate preventing any application of genome editing on the human germline until after a rigorous and thorough evaluation and discussion are undertaken by the global research and ethics communities," the researchers wrote in their paper.
"Since the technology is relatively simple, which indicates a low threshold to conduct gene editing research, necessary supervision is still needed," Gao Caixia, a research fellow at CAS' Institute of Genetics and Development Biology, told the Global Times.