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LONDON — Britain may allow a controversial technique to create babies using DNA from three people, a move that would help couples avoid passing on rare genetic diseases, the country’s top medical officer says.
The new techniques help prevent women with faulty mitochondria — the energy source in a cell — from passing on to their babies defects that can result in such diseases as muscular dystrophy, epilepsy, heart problems, and mental retardation.
For a woman with faulty mitochondria, scientists take only the healthy genetic material from her egg or embryo. They then transfer that into a donor egg or embryo that still has its healthy mitochondria but has had the rest of its key DNA removed. The fertilized embryo is then transferred into the womb of the mother.