The controversial technique, which uses IVF to take genetic material from three or four adults and create an embryo, is currently illegal. If the technique is legalised, leading scientists and ethicists have warned that it could cause medical risks for future generations, and have raised concerns about the potential for it to dehumanise relationships between children and parents. But supporters of the technique say it will help avoid mitochondrial disease, which is passed on from mother to child. Parliament will vote on final regulations for the technique next year.