Thursday, June 21, 2007

Scientists decry President Bush's veto of stem-cell bill

Senate may yet override decision, but House falls short of needed votes.

Meredith Wadman

For the second time in less than a year, President George W. Bush yesterday vetoed legislation that would lift restrictions on US federal funding for human embryonic stem-cell research. The bill, passed by the Senate and the House, allows government funding for research on stem cells derived from embryos that are left over at fertility clinics and slated for destruction. "I will not allow our nation to cross this moral line," Bush said.

Bush also announced that he had signed an executive order — without new money attached — directing the government to support research on stem cells derived without creating or destroying embryos. He cited as an "exciting" example of this, three recent papers reporting the reprogramming of mouse skin cells into cells that seem indistinguishable from embryonic stem cells (see 'Simple switch turns cells embryonic'). This work was only done in mice, and the cells came with associated problems that would make them unsafe for therapeutic use.

Scientists, scientific societies and congressional critics decried the veto and dismissed the executive order as a red herring. The American Association for the Advancement of Science said that the order "is not a substitute" for the vetoed bill and noted that the new approaches supported by the order seem to already be eligible for federal funding.

Not satisfactory

Kathrin Plath, a stem-cell biologist at the University of California, Los Angeles, said that Bush's order "doesn't satisfy me, because we have to study stem cells derived from fertility clinic embryos to understand what a human embryonic stem cell is all about." Plath, who was a senior author on one of the three recent papers referred to by Bush1, notes that her group's results haven't been reproduced with human cells yet. "Human reprogramming might just not work," she says.

Federal funding is currently limited to work on a score of human embryonic stem-cell lines derived before August, 2001.

A recent poll, published today in Science2, shows that 60% of more than 1,000 infertility patients responding to a survey would probably donate their unused embryos for stem-cell research rather then have them destroyed or donated to another couple. So should the bill succeed, there would probably be a large source of embryonic cells available for research.

The Senate is expected to try to override Bush's veto in the coming weeks, and may muster the two-thirds majority required to do so. The House of Representatives is several dozen votes short of a veto-proof majority.