The use of an IVF technique involving DNA from three people to create a baby has moved a step closer with a study that shows it is safe.
Scientists at Newcastle University are trying to help women who are at risk of passing on serious genetic disorders to have a healthy child.
Last year the UK approved laws to permit the procedure, which involves using donor DNA from a second woman.
The study in Nature found the technique will lead to normal pregnancies.
The process, known as “early pronuclear transfer” involves removing the parents’ key genetic material from an embryo within hours of fertilisation, leaving behind the woman’s faulty mitochondria.
The parental DNA, which contains all the key genes responsible for character and appearance, is then transferred into a donor woman’s embryo, which has its nucleus removed but contains healthy mitochondria.
Last year the UK became the first country to approve laws to permit the procedure.
A study involving more than 500 eggs from 64 donor women found that the new procedure did not adversely affect embryo development and significantly reduced the amount of faulty mitochondria being passed on.
Prof Doug Turnbull, director of the Wellcome Trust Centre for Mitochondrial Disease at Newcastle University and a co-author of the study, said: “This study using normal human eggs is a major advance in our work towards preventing transmission of mitochondrial DNA disease.”
Prof Mary Herbert, also from the centre, added: “We are optimistic that the technique we have developed will offer affected women the possibility of reducing the risk of transmitting mitochondrial DNA to their children”.