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Washington, D.C.
Parkinson’s Disease. Cancer. Spinal cord injury. Although these conditions are strikingly different, some scientists believe that human embryonic stem cells could form the basis for treating all of them. The scientific challenges, however, are great. So, too, is the ethical divide over stem cell research. Notable political leaders, theologians, and some others believe that using embryos for research is morally wrong.
The hot debate over stem cells--including new research, pending legislation, and fundamental philosophy--dominated the second Genetics Perspectives on Policy Seminar (GenePOPS), held November 8, 2005, at the Johns Hopkins University campus in Washington, D.C. The Genetics and Public Policy Center, supported by The Pew Charitable Trusts at Johns Hopkins University, hosted the seminar. It featured a panel of four speakers: Dr. Mina Alikani, a senior research scientist at Tyho-Galileo Research Laboratories; Dr. Kathy Hudson, director of the Genetics & Public Policy Center; Dr. William Hurlbut, a physician and consulting professor at Stanford University and a member of the President’s Council on Bioethics; and Dr. Laurie Zoloth, director of Northwestern University’s Center for Bioethics, Science and Society.
The stem cell debate has intensified in the past couple of years. Scientists have demonstrated that embryonic stem cells hold unique potential to replace tissue damaged by disease. These stem cells act as “master cells,” generating healthy, new cells for specific body tissues. But research progress has fueled the flames of debate, with some claiming that viable human embryos hold the same moral status as fully formed humans and thus cannot be destroyed for science.
The Bush administration has allotted the National Institutes of Health (NIH) limited federal funding to pursue stem cell research. Currently, however, researchers are legally banned from using Federal funds to create new stem cells using human embryos. Various Congressional bills, now pending, would either relax this ban, expand federal funding, or make other changes.
Can the moral divide on stem cells be bridged? During the seminar, scientists on the panel shared their efforts to understand—and possibly close--this gap. They and their colleagues are working to harvest stem cells without harming viable embryos--an attempt to satisfy ethical concerns over embryo status.
Nonviable embryos, for instance, could become an important resource for stem cells, according to Alikani. She proposes harvesting functioning stem cells from nonviable human embryos, or those with chromosomal or other abnormalities that would prevent embryo development. Fertility treatments and genetic testing frequently result in such nonviable embryos. One private genetics laboratory, Reprogenetics, has over the past decade generated almost 95,000 clinically unusable human embryos as part of its work in preimplantation genetic diagnosis, according to Alikani.
In another approach, Hurlbut recently proposed an alternative technique to harvesting stem cells from embryos: altered nuclear transfer. This technique involves artificially building a kind of partial embryo, containing only enough cellular machinery to generate embryonic stem cells unable to implant or grow in the womb. In one version of altered nuclear transfer, researchers might alter cells to delete, or silence, a critical development gene called Cdx2. The resulting cellular structure would be “like a model plane without the glue,” as Hurlbut put it. He added: “If we could produce such an entity, it would not be considered human. It would fail to organize sufficiently to be called a living being.” The overall goal of altered nuclear transfer, Hurlbut says, is to create a method of generating stem cells that is both morally acceptable and qualified for federal funding.
“The fact is, we’ve sequenced the human genome, sequenced proteins, and from here on out this research is about living organisms,” Hurlbut asserted. “This is a very hard subject. I’m trying to find solutions, such as altered nuclear transfer, that would satisfy the concerns of most people.”
Can scientific attempts to find an ethical middle ground on stem cell research succeed? During the seminar, Zoloth expressed doubt. By trying to create alternative sources for stem cells, she argued, researchers were searching for scientific solutions to a profoundly religious problem—that a person somehow resides in his/her DNA, and society thus has a duty to protect embryos as living entities. “Can science solve social or theological debates?” Zoloth asked the crowd.
Zoloth compared changing the definitional criteria of an embryo to the legal recognition, in recent decades, of “brain death”—a point at which patients cease to function normally. The scientific community pushed for a legal recognition of brain death, she added, partly so that brain dead patients could become organ donors, thus increasing the pool of available organs in a time of nationwide shortage. Despite religious objections, Zoloth said, brain death did indeed become a legal entity. Now, she added, similar policy maneuvering is taking place over stem cell research.
“The idea is to create a new ‘bright line’ across the complexity of biological phenomena and events,” Zoloth said. “Are these entities alive or not?”
Hudson, the Center’s director, wrapped up the panel discussion with several additional questions. Why are arguments over stem cell research so fiery? Is there a consensus position? Are we edging any closer to that consensus? No easy answers emerged. Equally important, Hudson emphasized, is broader American opinion. Nationwide, how do people think or feel about embryonic stem cell research? Early surveys on this point were inconclusive, due to variable wording, conflicting findings, and limited survey design.
Recently, the Genetics & Public Policy Center took an important step toward understanding the average American’s views, with a 2005 survey of more than 2,000 adults. The resulting report, “Values in Conflict: Public Attitudes on Embryonic Stem Cell Research,” is available online at www.dnapolicy.org.
Describing the survey results during the seminar, Hudson reported that two-thirds of survey respondents support human embryonic stem cell research. In fact, the survey revealed a subtle topography of the public’s attitudes, with only a small fraction (6 percent at each pole) of the public occupying the extreme positions that so frequently characterize the public and policy debate. Similarly, the public’s views about the moral status of embryos, and the relationship of those views to embryonic stem cell research policy preferences, are subtle. The survey showed that nearly the same number of Americans believes that an embryo in a Petri dish has no or low moral status (30 percent) as those who believe it has maximum moral status (28 percent). The remainder (42 percent) accord embryos some intermediate moral status.
Against this complex backdrop, stem cell research continues, both in private labs and NIH-funded academic institutions. In both scenarios, researchers are working hard to understand basic stem cell biology—and, they hope, fight debilitating disease. As Alikani puts it, “We still have so much to learn.”
Alikani's slides
Hurlbut's slides
Zoloth's slides
Hudson's slides
Video Link:
http://www.dnapolicy.org/video/genepops/110805/index.htm
