Developmental biologist Kathy Niakan has received permission from U.K. authorities to modify human embryos using the CRISPR/Cas9 gene-editing technology. Niakan, who works at the Francis Crick Institute in London, applied for permission to use the technique in studies to better understand the role of key genes during the first few days of human embryo development.

The Human Fertilisation and Embryology Authority (HFEA), which grants licenses for work with human embryos, sperm, and eggs in the United Kingdom, approved Niakan’s application at a meeting of HFEA's license committee on 14 January. The minutes of that meeting state that, “[o]n balance, the proposed use of CRISPR/Cas9 was considered by the Committee to offer better potential for success, and was a justified technical approach to obtaining research data about gene function from the embryos used.”

The debate about the ethics of editing embryonic genomes has raged for several years; critics say studies such as Niakan's could be the first step towards "designer babies" or even eugenics.

But many scientists today welcomed HFEA's decision. “I am delighted to hear that the HFEA have had the good sense to approve this important project," Peter Braude, an emeritus professor of obstetrics and gynecology at King’s College London, said in a statement distributed by the Science Media Center in London today. “Gene editing tools will allow fresh insights into the basic genetic mechanisms that control cell allocation in the early embryo. These mechanisms are crucial in ensuring healthy normal development and implantation, and when they go wrong might result in failure to implant or miscarriage. I await results with interest.”