The disagreements arise when you start talking about where those cells come from.
Most commonly, scientists work with adult stem cells, which are typically found in bone marrow and blood from umbilical cords discarded after childbirth. They are what is known as “multipotent cells” — that is, cells with the potential to turn into other types of cells. But therein lies their limit: They can transform only into a certain number of new cell types. Moreover, they are hard to isolate and work with.
More promising are stem cells taken from human embryos. They can develop into any type of cell in the human body — even, eventually, entire organisms. For certain disorders, such as diabetes, there is no other known way to produce replacement organ systems that might constitute a cure.
Embryonic stem cells are also hard to work with, but their biggest problem is an ethical one: They are harvested primarily from embryos left over from in-vitro fertilization procedures and — most controversially — from abortions. Because the embryos are destroyed either way, nearly all religious denominations reject such harvesting as an unacceptable taking of human life. So do many scientists.
The debate is bitter and rooted in fundamental values: Does the potential benefit of exploiting embryonic stem cells to cure diseases outweigh the moral repugnance many Americans have at how they are collected? Researchers and ethicists on all sides agree on one thing: The debate must be settled soon.
The worst case, they agree, is that because the questions are so complicated, it could take universities, biogenetic corporations and regulators years to reach a consensus. By then, it could be too late. Scientists in Europe and Asia, where such research is less politically charged, have already taken a lead in work on embryonic cells, and American scientists will have much to do to catch up or demonstrate that adult stem cells alone can provide the same benefits.
President Bush wades in
We are where we are today because of President Bush’s address to the nation on Aug. 9, 2001, when he announced his administration’s policy on embryonic stem cell research.
The president made a remarkable speech, explaining the arguments for such research even as he rejected most of them. In the end, he arrived at a compromise: The government would not ban the research, but neither would it fund work on “lines” of stem cells derived from embryos created after that date. In all, as many as 78 lines of usable cells would be eligible for research using federal funds.
But the president’s goal of de-politicizing the question was never met. Opponents tarred his policy as a “ban” on stem-cell science — even though it had no impact on privately or locally funded research, and even though it did not affect adult stem cells or those taken from cord blood at all, and even though it did not even halt the federally funded research that was already under way.
Both Sen. John Kerry, the Democrats’ 2004 presidential candidate, and his running mate, Sen. John Edwards, seized on the “ban” as an applause line in the campaign. The administration, they charged, preferred to score moralistic points at the expense of progress that could cure many horrible diseases.
Reframing the debate
On the other side, many in religious political movements adopted the policy as a proxy in the debate over abortion, the contention being that Bush’s announcement at least partly enshrined into federal law their argument that human life is formed upon fertilization.
When both sides of an argument begin with a good-vs.-evil outlook, even simple discussion becomes difficult.
Richard Doerflinger is deputy director for pro-life activities for the U.S. Conference of Catholic Bishops. He is one of the most forceful advocates for a ban on embryonic stem cell research.
“It’s the issue of destroying fellow members of the human species for their cells,” he said. “... You can’t point to many instances in human history where that process of dividing the human species came to any good.”
Aaron D. Nelson works on the tip of the cutting edge of the field as a research assistant to Clive N. Svendsen, the pioneering neurologist who directs the Stem Cell Research Program at the University of Wisconsin, where embryonic stem cells were first isolated 6½ years ago.
Nelson said researchers were not blind to the ethical qualms of those who see harvesting of embryonic stem cells as tantamount to homicide. But he said they had been falsely caricatured as soulless scientists who “have set up special abortion clinics just to get more embryos.”
“It’s difficult and frustrating,” Nelson said. The viewpoint of opponents “is not data-based. They don’t necessarily have the facts.”
Nobody’s happy now
At least one thing is clear about the president’s policy, said Eric Cohen, director of the Biotechnology and American Democracy Program for the Ethics and Public Policy Center: “It’s a pretty remarkable debate in that neither side is happy with the status quo.”
“Advocates for the research are unhappy because they believe it should have much more federal funding,” Cohen, whose institute opposes embryonic cell research, said in an interview. Meanwhile, “those who oppose embryo research are deeply unhappy because, at present, there are no limits on any kind of embryo destruction at all.”
For supporters of the research, the policy is especially troubling because of problems with the cell lines that were grandfathered in under Bush’s August 2001 deadline.
It is still an arduous task to develop usable cell lines from identified cultures, and only 22 of the 78 potential lines approved for federal funding are available after 3½ years, according to the National Institutes of Health. At least 18 others have already failed, leaving only 38 federally approved lines left to explore. Once those are exhausted, no more will be available to government scientists or those who rely on federal grants.
Worse, the usable lines may be too dangerous. All of the approved lines were grown using “feeder” cells from mice; that means, researchers say, that all of them could be contaminated with mouse viruses.
Here’s one of the many paradoxes: You can now grow new, safer human embryonic stem cells without using mouse feeders. But under the president’s policy, you’re barred from conducting research on them using federal money.
So supporters have turned to other sources of funding. Among the most generous have been large state governments.
Three of the most populous states — California, Massachusetts and New Jersey — have created foundations to push the science; California alone will distribute $3 billion through its Institute for Regenerative Medicine, with a priority on embryonic cell work.
America falling behind
Scientists say it is not an ideal solution. Research conducted without federal funding is also conducted without federal supervision or safety standards. Nor is it centralized in a federal database. There is no way to compel corporations, for example, to share their findings for the public good, rather than hoard them behind patents for proprietary profit.
The National Academy of Sciences issued guidelines last month for research on embryonic stem cells, recommending, among other things, restrictions on how long embryos should be allowed to grow (to make sure they don’t have time to develop a nervous system) and a ban on paying donors for embryos.
The guidelines were widely welcomed, and they are likely to be adopted by many institutions. But they are still only guidelines, and they can do nothing to increase funding for research.
In the meantime, there are signs that American scientists are falling behind.
Under the auspices of a national Consortium for Cell Therapy, Israeli scientists have already managed to grow heart cells from embryonic stem cells, for example, and Israeli companies are promising to produce new blood vessels and techniques to treat spinal cord injuries. And just last month, the European Union announced that its budget for embryonic stem cell research would double, to more than $88 billion, dwarfing the resources available to American scientists.
In the absence of federal support and consistent guidelines, American science can’t coordinate to compete. That means, supporters say, that if it is to benefit from the latest advances, the United States will have to rely on the goodwill of foreign governments that buy into embryonic cell work to provide applications that could fall short of basic American standards.
Worse, they warn, the flow of U.S. researchers following grants into private industry and even overseas threatens to create a “brain drain” with catastrophic consequences for American science.
“I think it’s a very legitimate problem. With the California initiative and here at [the University of Wisconsin], people are leaving to go where the money is,” Nelson said. “I personally would tend to do that myself. I would go where I could get funding with less restrictions.”
No crystal ball
Embryonic stem cell research offers potential for medical miracles. But it also confronts science with very real — some would say disqualifying — ethical questions. It could take the best minds of science, religion and civic society years to unlock that puzzle.
Doerflinger counseled erring on the side of caution. Embryonic stem cell research is too risky, and the moral costs are too high, he warned.
“What if we end up going out there and destroying all these embryos and desensitizing ourselves to the moral issues involved and finding we really did kill what we should recognize as human beings for not a lot of payoff?” he asked. “What do we say — ‘oops’?”
Cohen, a consultant to the President’s Council on Bioethics, said it’s not that cut and dried. “This will be a debate that continues for a very, very long time, because it cuts to the depth of the American character.”
“Two things that America prizes are, on the one hand, deep belief in human equality, the deep belief that all human beings” — which includes embryos, in this view — “have a basic dignity just by virtue of being human beings. On the other hand, there’s a very deep devotion, and rightly so, to technological and medical progress.
“We’ll maybe find some common ground on issues around the margins,” he said, but “I don’t see any dramatic policy change in the years ahead, which means embryo destruction will continue and those who oppose embryo destruction will continue to be vigorous in their opposition to it.”