Britain’s fertility regulator has approved a scientist’s request to edit the human genetic code in an effort to fight inherited diseases — but critics fear the new technique crosses too many ethical boundaries. The Human Fertilisation and Embryology Authority announced Monday it has granted a research application to a team led by scientist Kathy Niakan to try to understand the genes that human embryos need to develop successfully. Scientists say gene-editing techniques could one day lead to treatments for conditions like HIV, which causes AIDS, and inherited diseases like muscular dystrophy and sickle cell disease. Niakan, of the Francis Crick Institute, plans to use gene editing to analyze the first week of an embryo’s growth.

This research will “enhance our understanding of (in vitro fertilization) success rates, by looking at the very earliest stage of human development,” said Paul Nurse, director of the Francis Crick Institute. Peter Braude, an emeritus professor of obstetrics and gynecology at King’s College London, said the mechanisms being investigated by Niakan and colleagues “are crucial in ensuring healthy, normal development and implantation” and could help doctors understand how to improve in vitro fertilization rates and prevent miscarriages. FULL REPORT