With the votes in from the House of Lords, the UK is the first country to allow the creation of human embryos using mitochondrial donation, an approach dubbed "three-person IVF" as nuclear DNA would come from the mother and father while a donor would provide mitochondrial DNA, as the Guardian reports.
Such an approach, proponents say, would prevent incurable mitochondrial diseases from being passed on from mother to child, while critics argue that it is akin to playing God and could lead to the advent of designer babies.
The House of Commons passed the bill allowing the procedure earlier this month, while the House of Lords took it up this week.
"Families who know what it is like to care for a child with a devastating disease are the people best placed to decide whether mitochondrial donation is the right option for them," says Jeremy Farrar, the director of the Wellcome Trust. "Parliament is to be commended for a considered and compassionate decision to give these families that choice, with proper safeguards under the UK's internationally-admired regulatory system."
The AP notes that the procedure would likely only be used to help about a dozen British women a year, and the Guardian says that fertility clinics can begin to apply for licenses in the fall.