Whatever the reason – building a portfolio for a presidential run or true medical concern – Senate Majority Leader Bill Frist’s announcement last week to break from the president and support an expansion of federal funding for embryonic stem cell research was a significant breakthrough. Sen. Frist’s support should encourage other lawmakers to support a bill that could lead to gains in treating diseases such as diabetes and Parkinson’s. It should also prompt the White House to reconsider its stance.

In a floor speech shortly before the Senate summer recess, Sen. Frist said that the president’s policy of limiting federal research dollars to just those stem cell lines in existence in August 2001 needed to be changed. “While human embryonic stem cell research is still at a very early stage, the limitations put in place in 2001 will, over time, slow our ability to bring potential new treatments for certain diseases,” the Tennessee Republican told his colleagues. “Therefore, I believe the president’s policy should be modified.”

When the president announced his policy to limit funding to existing embryonic stem cell lines, it was believed that 78 lines were available. This was not the case and only 22 lines are now eligible for federal funding. Over time, these lines become less stable and harder to replicate. They are also derived from mouse feeder cells which limits their potential for clinical therapy in humans.

Further, Sen. Frist, a heart-lung transplant surgeon, said that while adult stem cells can be used to treat some diseases, they are not as flexible and promising as embryonic stem cells which can become almost any human tissue.

So, Sen. Frist said he would favor an expansion of federal funding so researchers could use embryos that are left over from fertility treatments and are being discarded now. A bill to do this has passed in the House but stalled in the Senate. Sen. Frist should now turn his convictions into action by encouraging fellow Republicans to support the bill and by bringing it up for a vote.

The next hurdle is the White House. President Bush has threatened to veto such a bill. A White House spokesman said the president had made his position clear in the past and that the president stood on the principle to protect life.

Sen. Frist addressed such concerns as well. “An embryo is nascent human life,” he said on the Senate floor. But, he added, “This position is consistent with my faith. But, to me, it isn’t just a matter of faith. It’s a fact of science.”

The fact is that the science of stem cells will proceed with or without federal funding, but may not happen as quickly, and is less likely to be developed in the United States or under federal standards if the limited use of cell lines approved by the president

in 2001 remains in effect.

This debate is not about cloning or when life begins. Instead, it is about whether U.S. researchers, practicing under broadly accepted ethical standards, are going to lead the field of stem cell science or follow it, and what the implications for Americans suffering from diseases some day treatable through this research will be.

With a push from Sen. Frist, the debate is now moving in the right direction.