Scientists in Britain have been given the go-ahead to edit the genes of human embryos for research, using a technique that some say could eventually be used to create "designer babies". Less than a year after Chinese scientists caused an international furore by saying they had genetically modified human embryos, Kathy Niakan, a stem cell scientist at London's Francis Crick Institute, was granted a licence to carry out similar experiments."The Human Fertilisation and Embryology Authority has approved a research application from the Francis Crick Institute to use new gene editing techniques on human embryos," Niakan's lab said yesterday.It said the work "will be for research purposes and will look at the first seven days of a fertilised egg's development, from a single cell to around 250 cells".Niakan plans to experiment using CRISPR-Cas9, a technology already the subject of fierce international debate because of fears that it could be used to create babies designed to order.CRISPR enables scientists to find, and modify or replace, defective genes.David King, director of the UK campaign group Human Genetics Alert, has called Niakan's plans "the first step on a path towards the legalisation of GM babies".Niakan says she has no intention of genetically altering embryos in human reproduction but wants to deepen scientific understanding of how a healthy human embryo develops, which could, in the long term, help to improve infertility treatments.At a briefing for reporters in London last month, she said the first gene she planned to target for examination was Oct4, which she believes might have a crucial role in the earliest stages of human foetal development.Bruce Whitelaw, a professor of animal biotechnology at Edinburgh University's Roslin Institute, in Scotland, said the decision had been reached "after robust assessment". ..