A controversial bill to extend the research uses of human foetal cells was rejected by Parliament this week, writes Alan Thomson.
Liberal Democrat higher education and science spokesman Evan Harris, a medical doctor, brought his motion for a stem cell research bill before the Commons on Tuesday, under the ten minute rule.
The motion was defeated by 175 votes to 83.
Dr Harris told MPs that the only source of appropriate stem cells available, at present, is from embryos up to 14 days after conception.
Stem cells in early human foetuses develop to form the full range of body cells.
The idea is that stem cells can be grown to produce replacement cells and tissue for people suffering from a range of diseases, including Parkinson's and heart disease, as well as those with organ failure and cancer. Dr Harris said it was essential, therefore, to allow limited research on stem cells.
He told MPs there was no intention of using embryos as the source of cells to cure disease, but that research on embryonic stem cells was necessary to further understanding of how adult stem cells could be derived.
He said that embryos of up to 14 days were smaller than the head of a pin, and he added there was no question of experimenting on anything that remotely resembled a foetus or had any sentient life.
Speaking against the motion, Conservative MP Edward Leigh described the use of early embryonic tissue, or as he said "unborn children", for their cells as "morally and ethically repugnant".
Mr Leigh said it was impossible to say when a foetus stops becoming just a collection of cells and starts to become a human.
"The only logical and ethical conclusion is that life begins at conception," he said.
The government has said it intends to extend the Human Fertilisation and Embryology Act 1990 to allow the use of embryonic cells in research aimed at curing disease.