Mark and Luke Borden were excess embryos in a fertility clinic when their parents decided to adopt them.
The two embryos _ now 9-month-old twins _ had been left over after their genetic parents conceived using in vitro fertilization. And, like most embryos, they were eventually to be discarded.
Instead, the embryos were implanted in Lucinda Borden, who said the chance to experience pregnancy and childbirth made her favor adopting the embryos over traditional adoption.
On Tuesday, the twins became poster children for a new front in the movement against embryonic stem cell research.
John Borden held a barefoot son in each arm and faced a House subcommittee.
"Which one of my children would you kill?" he asked. "Would you take Luke the giggler? Or would you take the big guy, Mark?"
The adoption of the children from excess embryos puts yet another human face on the heated debate surrounding federal funding of embryonic stem cell research, which many scientists say could lead to cures for countless diseases, including Parkinson's, Alzheimer's and diabetes.
Advocates have long argued that such research, which must destroy embryos to extract stem cells, would use only embryos that would otherwise be discarded at fertility clinics. Adopted embryos challenge that assumption. In the eyes of those who are opposed to embryonic stem cell research, the freezers of fertility clinics are "frozen orphanages."
Recognizing the emotional appeal of such witnesses, both sides of the debate enlisted children Tuesday.
At a news conference across the street from the subcommittee hearing, 12-year-old twins Mollie and Jackie Singer of Las Vegas talked about Mollie's struggle with juvenile diabetes.
Mollie said she developed diabetes when she was 4 and had open heart surgery when she was 5. "I don't want Jackie or anyone else to go through what I've been through," she said. "Please support the" National Institutes of Health "guidelines for embryonic stem cell research."
Her sister spoke afterward: "I don't want Mollie to go blind, I don't want her to have kidney failure, and I don't want her to have a heart attack or a stroke. . . . All Mollie wants to do is live a normal, healthy life, and embryonic stem cell research is our best hope."
President Bush is expected to decide in the coming weeks whether to allow federal funding for research on stem cells taken from human embryos, a process he opposed in his campaign. The Clinton administration allowed some stem cell research, but not as much as many scientists desired.
In the atmosphere of uncertainty, publicly funded research of stem cells has slowed, though labs funded by biotech firms and other private money continue to study embryonic stem cells.
Scientists at the Jones Institute for Reproductive Medicine in Norfolk, Va., last week announced they had created human embryos exclusively for stem cell research, rocking a tacit consensus among researchers to use only frozen embryos that would otherwise be discarded.
One of the nation's leading stem cell researchers, Roger Pedersen of the University of California at San Francisco, announced this week that because of the federal government's lack of support for the research, he is leaving to work in Britain. Many fear that others will follow suit.
"This research holds out promise for more than 100-million Americans suffering from a variety of diseases, including heart disease, multiple sclerosis, Parkinson's, Alzheimer's, ALS, cancer, and diabetes," said Sen. Orrin Hatch, R-Utah, testifying at Tuesday's House hearing.
"While I have no objection to considering ways to foster adoption of embryos, there are a host of issues associated with this which must be worked out," said Hatch, who favors such research despite his strong anti-abortion stance.