British lawmakers have approved plans to allow scientists to use hybrid animal-human embryos for stem cell research, the Associated Press reported.
The House of Commons also clarified laws which allow the screening of embryos so parents can produce babies genetically matched to sick siblings.
Legislators voted 355 to 129 Wednesday to authorize the proposals. The vote followed months of debate that has pitted Prime Minister Gordon Brown's government and scientists against religious leaders, anti-abortion campaigners and others anxious about medical advances.
The new laws also clarify rules on cases where parents seek to have a child with specific characteristics to help a diseased older sibling through tissue or organ donation.