A team of Chinese scientists said they successfully tweaked human DNA in an embryo for the first time in history, according to a new paper published in the online journal Protein & Cell.
Huang Junjiu, an associate professor of biology at Sun Yat-sen University in Guangzhou, led a team of researchers who managed to alter a gene in a non-viable embryo (embryos that cannot result in live birth) that would’ve been responsible for β-thalassaemia, a potentially deadly blood disorder common among children in southern China.
According to Business Insider:
CRISPR, the technology that makes all this possible, can find bad sections of DNA and cut them and even replace them with DNA that doesn’t code for deadly diseases, but it can also make unwanted substitutions. Its level of accuracy is still very low.
Huang’s group successfully introduced the DNA they wanted in only “a fraction” of the 28 embryos that had been “successfully spliced” (they tried 86 embryos at the start and tested 54 of the 71 that survived the procedure). They also found a “surprising number of ‘off-target’ mutations,” according to Nature News.
Huang told Nature News that they stopped then because they knew that if they were do this work medically, that success rate would need to be closer to 100%.
Scientists have argued that the human genome should not be edited because it’s ethically questionable.
Edward Lanphier, a British biologist, said in a Nature article that “we need to pause this research and make sure we have a broad based discussion about which direction we are going here.”
The research has been seen as a breakthrough among the scientific community in China, however, and biologists here have defended Huang and his colleagues, calling the critics’ statements arbitrary.
“To do as they said, no research should be done on human embryos at all,” Chen Guoqiang, a professor of biology at Tsinghua University, said in an SCMP report.
“The breakthroughs in this field of research will eventually benefit every one of us. The editing of human DNA holds the key to cure many diseases, maintain health, retain youth, live long. These will all be possible in the future and free many families from pain and sufferings.”
“They are only experimenting with non-viable embryos. The research is far, far away from clinical application or commercial use,” said Zhao Shimin, a biologist with Shanghai’s Fudan University. He added, however, that there are risks that come with the technology.
“While such studies should be allowed, they must be strictly kept inside labs. Massive, uncontrolled use of DNA editing could lead to the extinction of the human race.”
The paper was originally submitted to the journals Nature and Science but was turned down due to “ethical objections,” according to Huang. He wants to continue improving the accuracy of CRISPR using animal models.