Declining to name the parents of the children or offer any independent verification of the work, there is still skepticism that He, who has degrees from Stanford and Rice, has actually done it. Cases of scientific fraud in high-stakes breakthroughs, like South Korean researcher Woo Suk Hwang's cloning claims, still loom large. But if He has genetically altered the two children, it is a monumental step forward for CRISPR technology.
“I feel a strong responsibility that it’s not just to make a first, but also make it an example,” he said. As for laws governing genetic engineering, He says, “society will decide what to do next.”
CRISPR's potential to treat serious diseases has been known for years, although scientists are unsure how many people are actually immune to the procedure.
He claims that he chose the HIV virus, the infection that can lead to AIDS, because the disease is a growing problem in China. In September, the Chinese government announced a 14 percent rise in the number of citizens living with HIV or AIDS, with 40,000 new cases reported in the second quarter of 2018. He has also put out a series of YouTube videos describing his reasoning for choosing to focus on HIV as well as the ethics of his actions.
He claims to have edited the embryos of seven couples during in vitro fertilization (IVF), in which an egg and sperm are combined outside the body. In all seven cases, the men had HIV and the women did not. The couples were recruited through an AIDS advocacy group called Baihualin, which works against societal discrimination of those infected with the disease.
He focused on disabling a gene well-known to HIV researchers: CCR5, a protein on the surface of white blood cells. HIV commonly uses the CCR5 protein to enter cells. By disabling the CCR5 doorway, He's work would block off one of the HIV virus's most common routes of infection.
Genetic alternations made during the IVF stage can be inherited by future children, the prospect of which has made such testing illegal in the United States. While China has laws outlawing cloning, no such regulations prevent gene editing.
Laws aside, the announcement has been met with severe backlash across the scientific community. Focus has been not just on general morality but also on He's choice of target. While CCR5 is a gateway for HIV, it also works to prevent mosquito-associated diseases like West Nile virus.
In a strenuous statement, one of the inventors of CRISPR technology, Feng Zhang of MIT and Harvard, said that, "Although I appreciate the global threat posed by HIV, at this stage, the risks of editing embryos to knock out CCR5 seem to outweigh the potential benefits, not to mention that knocking out of CCR5 will likely render a person much more susceptible for West Nile Virus. Just as important, there are already common and highly-effective methods to prevent transmission of HIV from a parent to an unborn child."
"Given the current state of the technology, Feng continues, "I'm in favor of a moratorium on implantation of edited embryos, which seems to be the intention of the CCR5 trial, until we have come up with a thoughtful set of safety requirements first."(DWK)