VIDEO: Green Light for Human-Animal Embryos

British lawmakers reject calls to ban the creation of human-animal embryos for research.

Brothers Charlie and Jamie Whitaker have a special bond. Jamie was conceived specifically so his stem cells could be used to save his elder brother who had a rare blood disease.

"I couldn't make my own blood cells and Jamie gave me his to help make my own," says Charlie Whitaker.

Britain's lawmakers have controversially voted to back the use of artificial insemination to select such 'saviour siblings'.

The boys' parents, who had to go to the U.S. to achieve their goal, deny they created new life for medical expediency.

The boy's mother, Michelle Whitaker, defended the claim saying: "We wanted to have more children. Jamie is loved for Jamie, not because of what he did for Charlie. That's the extra thing he did for him but Jamie is loved for himself."

In a separate controversial vote the UK Parliament also blocked a move to ban the creation of human-animal embryos for research.

Some scientists say such embryos are vital to find cures for diseases but critics fear they pervert the course of nature.

While the ethics-versus-science debate is far from over in Britain, stem cell research is banned by many countries including Australia, France, Italy and Germany.

The practice is also under fire from some religious leaders, one Catholic cardinal has called such work Frankenstein science.