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Green Light for Research on Stem Cells From Surplus Embryos

More on NIH's draft guidelines on stem cells.

On 9 March, Obama signed an executive order that lifted the Bush Administration's bar on funding for lines derived after 9 August 2001. But Obama's order left it to the National Institutes of Health to work out the details, leaving unanswered the critical question of where the embryos could come from. Many researchers would have preferred to have the freedom to work not only on leftover embryos from fertility clinics but also on human embryonic cell lines derived from embryos created for research purposes—for example, from the skin cell of a patient with a disease, so that researchers could then use the cell line to study the disease in test tube experiments.

But NIH decided not to include embryos created specifically for research, despite support from many scientists to do so. NIH Acting Director Raynard Kington explained to reporters on a conference call today that "there's strong, broad support" for allowing research on cell lines from surplus embryos from fertility clinics, as shown by legislation that passed Congress twice. "There's not similar broad support for using the other sources," he said, adding that "we don't believe that there is yet even consensus within the scientific community." Moreover, Kington pointed out, cell lines created through research cloning don't yet exist.

Even with the limitations, Kington predicted that "in a matter of months, we are likely to increase greatly the number of human embryonic stem cell lines eligible for federal funding including cell lines exhibiting greater genetic diversity and lines with disease-causing mutations." He said NIH estimates that up to 700 lines exist, although the number that qualify depends on how many comply with the draft policy. Proposals already submitted to NIH will be put on hold for review until the final guidelines are out.

The draft rules list several conditions that a cell line must meet to be eligible, most involving obtaining informed consent so that couples receiving fertility treatment are not induced to donate their spare embryos. The policy does not specify that the embryos have to be frozen rather than fresh, a possible restriction that worried some scientists.