16:44 02 February 2016
In a world-first, UK scientists have obtained the go-ahead by the fertility regulator allowing them to genetically modify human embryos.
The DNA-altering technique in embryos will be performed at the Francis Crick Institute in London and it aims to provide a deeper understanding of the earliest moments of human life. However, scientists are prohibited to implant the modified embryos into a woman.
The decision has attracted controversy over concerns it is opening the door to designer or GM babies.
Last year, scientists in China have announced they had carried out gene editing in human embryos to correct a gene that causes a blood disorder.
Prof Robin Lovell-Badge, a scientific advisor to the UK's fertility regulator, said: "China has guidelines, but it is often unclear exactly what they are until you've done it and stepped over an unclear boundary.
"This is the first time it has gone through a properly regulatory system and been approved."
Dr Kathy Niakanm, who will lead the experiment, said: "The reason why it is so important is because miscarriages and infertility are extremely common, but they're not very well understood."