The government issued final rules Monday expanding taxpayer-funded research using embryonic stem cells, easing scientists' fears that some of the oldest batches might not qualify and promising a master list of all that do.
President Obama lifted restrictions on the field in March, but he left it to the National Institutes of Health to decide what stem cell research was ethically appropriate: only science that uses cells culled from leftover fertility clinic embryos -- ones that otherwise would be thrown away, the agency made clear in draft guidelines.
But the final rules settle a big question: Would new ethics requirements disqualify many of the stem cells created over the last decade, even the few funded under the Bush administration's tight limits?
The NIH came up with a compromise, saying it deems those old stem cell lines eligible for government research dollars if scientists can prove they meet the spirit of the new ethics standards. NIH will also create a registry of qualified stem cells so scientists don't have to second-guess.
"We think this is a reasonable compromise to achieve the president's goal of both advancing science while maintaining rigorous ethical standards," acting NIH Director Raynard Kington said Monday. "We believe that judgment is necessary."
Scientists welcomed the change.
"I expect that most existing lines will be found to have been ethically derived," Dr. Sean Morrison, director of the University of Michigan Center for Stem Cell Biology, told the Associated Press. "This will eventually make hundreds of new stem cell lines available for use."
The issue: Trying to harness embryonic stem cells -- master cells that can morph into any cell of the body -- to create better treatments, maybe even cures, for such ailments as diabetes, Parkinson's and spinal cord injury.
Culling those stem cells destroys a days-old embryo, which many strongly oppose on moral grounds. Once created, those cells can propagate indefinitely in lab dishes.
The Bush administration had limited taxpayer-funded research to a small number of stem cell batches, or lines, already in existence as of August 2001. This spring, Obama lifted that restriction, potentially widening the field -- there now may be as many as 700 stem cell lines around the world -- but letting NIH set its boundaries.
NIH sifted through 49,000 comments from the public in finalizing the rules, which take effect today.
Opponents of stem cell research criticized the move.
"These guidelines encourage researchers to go out and destroy embryos for taxpayer-funded research," Richard Doerflinger, associate director of Pro-life Activities at the U.S. Conference of Catholic Bishops, told the Washington Post.