An attempt to ban the use of interspecies or hybrid embryos for stem cell research was defeated in the UK’s House of Commons last night.

MPs, including Labour Catholics who are uneasy about the provisions for human admixed embryos in the government’s Human Fertilisation and Embryology Bill, had a free vote on the issue. An amendment to ban the practice, led by Conservative MP Edward Leigh, was defeated by a vote of 336 to 176. Another amendment, which would have outlawed the use of ‘pure’ (i.e., as much as 50% animal) hybrids, was also defeated, by a vote of 286 to 223.

The controversial provisions were debated at the committee stage of the Human Fertilisation and Embryology Bill’s passage through Parliament, following a second reading in the House of Commons earlier this month.

Over the weekend, Prime Minister Gordon Brown nailed his colours to the mast with an article in The Observer newspaper arguing unequivocally that scientists should be given “the legal framework they say they need to pursue new cures and treatments through stem cell research”.

If we “want to sustain stem cell research and bring new cures and treatments to millions of people, I believe admixed embryos are necessary”, Brown wrote. “The question is not whether they should exist, but how their use should be controlled.”