Babies made from two women and one man will be born in the UK from as early as next year.The UK's fertility treatment regulator, the HFEA , has today approved the use of Mitochondrial Replacement Therapy (MRT) "in certain, specific cases." This advanced form of IVF allows scientists to replace abnormal genes in a mother's mitochondria with safer genes from another woman.Though this pioneering technique will be used to prevent mitochondrial disease, which can be extremely debilitating and even fatal, each baby born using MRT will only receive 0.1% of its DNA from the mitochondrial donor. Because of this, some scientists have argued that the term "three-parent baby" is actually highly misleading."Today’s historic decision means that parents at very high risk of having a child with a life-threatening mitochondrial disease may soon have the chance of a healthy, genetically related child. This is life-changing for those families," said the HFEA's Chair, Sally Cheshire.The BBC reports that the HFEA will have to approve every fertility clinic which wishes to perform MRT, as well as each individual case where MRT is sought. Only cases in which the risk of a child developing mitochondrial disease is "very high" will be given the go-ahead.The fertility team at Newcastle-upon-Tyne Hospitals NHS Foundation Trust and Newcastle University is expected to be the first to be granted a licence. The first baby born in the UK using MRT will be welcomed in late-2017, at the earliest.A baby born using the technique was welcomed in the U.S. earlier this year, the BBC reports, and is understood to be healthy.