Recent research should make it possible to create children who have not two, but three parents.
Doctors are a step closer to creating babies with DNA from three people after research on healthy embryos found the procedure was likely to produce normal pregnancies.
Studies on embryos made with extra DNA showed that the majority were indistinguishable from standard IVF embryos, although further tests hinted that the procedure still carried risks.
The work will be reviewed by the UK government’s fertility regulator, which is expected to make a recommendation on whether or not to approve the treatment under licence before the end of the year.
In PNT, the mother’s egg is fertilised with the father’s sperm using standard IVF procedures. Before the egg has a chance to divide into two cells, the parents’ chromosomes are plucked out and dropped into a fertilised egg from a healthy donor, which has had its own chromosomes removed.