Fifty-eight senators have signed a letter to President George W. Bush calling for an expansion of the federal policy that limits the funding for human embryonic stem cell research. The letter, which is similar to the one sent to the President in late April by members of the House (C&EN, May 3, page 22), illustrates the bipartisan congressional support for changing the current policy that strictly limits the number of stem cell lines available for federally funded research. "Scientists have told us that since the policy went into effect more than two years ago, we have learned that the embryonic stem cell lines eligible for federal funding will not be suitable to effectively promote this research," the senators wrote. The letter also notes the senators' willingness to work with the President to modify the stem cell policy. "We should not close the door on a form of scientific research--nuclear transplantation--that has the potential of curing millions of debilitating and life-threatening diseases," said Sen. Orrin G. Hatch (R-Utah), one of the cosponsors of the letter.