"Are you a member of a pro-life (search) committee?" Sen. Frank Lautenberg, D-N.J., asked a scientist who testified that adult stem cells work at least as well as embryonic stem cells in experimental treatments for some diseases.
Dr. Jean Peduzzi-Nelson of the University of Alabama at Birmingham did not directly answer that question. "Whether I'm pro-life or pro-choice, I wish all these types of things could be kept out of the discussion," she told the Senate Commerce science subcommittee.
Yet in her prepared testimony, Peduzzi-Nelson wrote, "There is no doubt that President Reagan would not favor federal support of research using human embryos."
Sen. Sam Brownback, R-Kan., the subcommittee chairman, has questioned the ethical propriety and necessity of embryonic stem cell research. He said the hearing would focus only on stem cells taken from adults, about which there is no controversy. "This is a good news hearing," he said.
Many scientists, however, consider embryonic stem cells much more versatile than adult cells.
Embryonic stem cells are master cells that form during the early days after conception and can turn into any tissue in the body. Many scientists hope to one day harness them to grow replacement tissue to treat diabetes, spinal cord injuries and other afflictions.
Culling stem cells kills the embryo, though, so many religious groups oppose the process. President Bush has ordered the National Institutes of Health not to fund any research on such cells harvested after Aug. 9, 2001.
Former first lady Nancy Reagan has called for the restrictions to be lifted, and last month 58 senators from both parties made the same request.
Robert Goldstein, chief scientific officer of the Juvenile Diabetes Research Foundation International, said the embryonic cells show much more promise for treating diabetes than adult cells do.
"Pursue both avenues simultaneously and with equal vigor," Goldstein said.
Irving Weissman, a Stanford University scientist and a leading advocate of embryonic stem cell research, also said both approaches hold tremendous promise.
At the hearing Wednesday, two women with spinal cord injuries testified about the progress they have made after receiving experimental treatment with adult stem cells. Susan Fajt of Austin, Texas, and Laura Dominguez of San Antonio are among a handful of people who have traveled to Portugal for the treatment, in which cells from their noses were transplanted to their spinal cords.
"I have come farther than my American doctors ever thought," Fajt said.
Dennis Turner, a southern Californian with Parkinson's disease, also told the panel how his symptoms disappeared for a while after he received treatment with stem cells.
Turner's doctor, Michel Levesque, said Turner is the only patient who has received the treatment, but he hopes to repeat the procedure in 15 more Parkinson's patients.