The first baby conceived using DNA from three different people may be born as early as next year.
Peers yesterday voted to make the UK the first country in the world allowing the creation of in vitro fertilisation (IVF) babies using three parents.
The procedures are aimed at preventing serious inherited mitochondrial diseases.
A three-parent child would have "nuclear" DNA determining individual traits such as facial features and personality from its two parents, plus a tiny amount of mitochondrial DNA (mDNA) from an anonymous woman donor.
Opponents, including church leaders and pro-life groups, have warned that the change has been brought about too hastily and marked the start of a "slippery slope" towards designer babies and eugenics.
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