Russian biologist plans more CRISPR-edited babies

A Russian scientist says he is planning to produce gene-edited babies, an act that would make him only the second person known to have done this. It would also fly in the face of the scientific consensus that such experiments should be banned until an international ethical framework has agreed on the circumstances and safety measures that would justify them.

Molecular biologist Denis Rebrikov has told Nature he is considering implanting gene-edited embryos into women, possibly before the end of the year if he can get approval by then. Chinese scientist He Jiankui prompted an international outcry when he announced last November that he had made the world’s first gene-edited babies — twin girls.

The experiment will target the same gene, called CCR5, that He did, but Rebrikov claims his technique will offer greater benefits, pose fewer risks and be more ethically justifiable and acceptable to the public. Rebrikov plans to disable the gene, which encodes a protein that allows HIV to enter cells, in embryos that will be implanted into HIV-positive mothers, reducing the risk of them passing on the virus to the baby in utero. By contrast, He modified the gene in embryos created from fathers with HIV, which many geneticists said provided little clinical benefit because the risk of a father passing on HIV to his children is minimal.