The battle over stem cells has long been polarized to the detriment of science. Now, there are encouraging signs that the scientific benefits of the embryonic cells are moving to the forefront of the policy debate.

The subtle change is found in one sentence in a recent lengthy letter to members of Congress from the head of the National Institutes of Health, Elias Zerhouni. The doctor wrote: “And although it is fair to say that from a purely scientific perspective more cell lines may well speed some areas of human embryonic stem cell research, the president’s position is still predicated on the belief that taxpayer funds should not ‘sanction or encourage further destruction of human embryos that have at least the potential for life.'”

The words certainly don’t signal a complete turn-around in administration policy, but as Rep. Michael Castle says, they represent “an invitation to have further discussions.”

Such discussions are urgently needed to reverse a government policy that puts philosophy, often rooted in religious conviction, ahead of science and medicine. Rep. Castle, a Delaware Republican, is leading an effort in the House of Representatives to change the current policy. So far, 206 members, including Maine’s Tom Allen, have signed on to the policy change push. A similar effort is under way in the Senate, with 50 members including both of Maine’s senators, signing on.

Rep. Castle and others will meet with White House officials this week to seek a compromise that will allow more research while not negating the president’s ethical concerns about the viability of embryonic cells. One possible solution is to allow research on embryos left over from in vitro fertilization attempts that would be destroyed anyway.

Saying embryonic stem cells have the potential for life, President Bush in 2001 banned the use of federal funds for research on stem cell lines derived after Aug. 9 of that year. The policy restricts research to 19 lines of existing embryonic stem cells. Scientists say these lines are not sufficient to sustain research. Stem cells have the potential to treat disabling and deadly diseases such as Alzheimer’s, Parkinson’s, multiple sclerosis, heart disease, cancer and others that affect more than 100 million Americans. Research in the United States into these and other illnesses and injuries that may be treated with stem cell therapy is now falling behind work being done in South Korea and other countries without such restrictions. To overcome the ban, Harvard University is in the midst of a $100 million fundraising campaign to establish a privately supported stem cell research institute and a measure will appear on the California ballot this fall seeking $3 billion for stem cell research over the next 10 years.

Republicans have been emboldened in this effort to change the prohibition by recent comments from Nancy Reagan. “I just don’t see how we can turn our backs on t his,” Mrs. Reagan said at a May 8 gala event to raise private money for stem cell research. Her husband, former president and conservative icon Ronald Reagan, has suffered from Alzheimer’s disease for more than a decade.

As Mrs. Reagan said, too much time has been lost on the political debate over stem cells. It is now time to put politically driven philosophy aside and move ahead with much-needed scientific research.