More setbacks to US stem cell research

Scientists have told delegates at an international biotechnology conference in Toronto, Canada, that fewer than half of the embryonic stem cell lines authorised for use by President Bush last summer will 'turn out to be viable in practice'.

President Bush gave permission for American government-funded American researchers to use stem cell lines already derived from human embryos, but not to derive embryo stem cell lines themselves. A list of such stem cell lines was provided by the National Institutes of Health (NIH), which said there were 80 viable stem cell lines from 14 different sources around the world.

However, scientists at the Toronto conference have claimed that fewer than half of these lines would be of the required quality for research, and may soon be 'made redundant' by new cell lines being created elsewhere by scientists not dependent on US government funding.

One problem is that cell lines have previously been developed alongside mouse cells. Dr Alan Colman, of ES Cell International, Singapore, said that researchers based there have discovered how to grow human embryonic stem cells without mouse cells. But any cell lines developed there would be unavailable to US state-funded researchers.