Chinese researchers experiment with making HIV-proof embryos

The scientists cautioned that they believe making actual genetically modified babies should be “strictly prohibited”—but perhaps only until the technology is perfected. “We believe that is necessary to keep developing and improving the technologies for precise genetic modification in humans,” Fan’s team said, since gene modification could “provide solutions for genetic diseases” and improve human health.

The Chinese scientists tried to make human embryos resistant to HIV by editing a gene called CCR5. It’s known that some people possess versions of this gene which makes them immune to the virus, which causes AIDS. The reason is they no longer make a protein that HIV needs to enter and hijack immune cells.

Doctors in Berlin demonstrated the effect after they gave a man sick from HIV a bone marrow transplant from a person with the protective gene mutation. The man—known since as the “Berlin patient”—was cured of HIV, too.

Using the gene-editing method called CRISPR, Fan and his team tried to change the DNA in the embryos over to the protective version of the CCR5 gene in order to show, in principle, that they could make HIV-proof people.