US scientists say a human and animal trial of a controversial new IVF treatment has yielded promising results.
The findings in Nature magazine show healthy-looking embryos can be created from a mix of three adult donors.
Human embryos were grown in the lab and some appeared normal, while monkeys born using the same technique remained fit and well, now aged three.
A public consultation on the ethics of using this IVF in the UK is under way.
Its findings will be reported to the health secretary in spring 2013.
The technique is designed to prevent debilitating and fatal “mitochondrial” diseases, which are passed down only from mother to child and which cause muscle weakness, blindness and heart failure.