Stem Cells: The Hope And The Hype

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Trapped in all this are patients and voters who struggle to weigh the arguments because the science is dense and the values tangled. Somewhere between the flat-earthers who would gladly stop progress and the swashbucklers who disdain limits are people who approve of stem-cell research in general but get uneasy as we approach the ethical frontiers. Adult-stem-cell research is morally fine but clinically limiting, since only embryonic cells possess the power to replicate indefinitely and grow into any of more than 200 types of tissue. Extracting knowledge from embryos that would otherwise be wasted is one thing, but scientists admit that moving forward would require a much larger supply of fresh, healthy embryos than fertility clinics could ever provide. And once you start asking people about creating embryos for the purpose of experimenting on them, the support starts to slow down.

So where do things stand, five years after Bush provided the first federal funding but radically limited how it could be used?

HOW RED TAPE SLOWED THE SCIENCE

In a prime-time speech from his Texas ranch in August 2001, Bush announced that federal money could go to researchers working on ESC lines that scientists had already developed but no new lines could be created using federal funds. "There is at least one bright line," he declared. The speech was a political and scientific landmark. It gave Democrats that rare gift: a wedge issue that split Republicans and united Democrats, who declared themselves the party of progress. Five years later, with midterms looming, they hope to leverage the issue as evidence that they represent the reality-based community, running against the theocrats. States from Connecticut to California have tried to step in with enough funding to keep the labs going and slow the exodus of U.S. talent to countries like Singapore, Britain and Taiwan. Meanwhile, private biotech firms and research universities with other sources of funding are free to create and destroy as many embryos as they like, because they operate outside the regulations that follow public funds.

For scientists who choose to work with the approved "presidential" lines, the funding comes wrapped in frustration. Today there are only 21 viable lines, which limits genetic diversity. They are old, so they don't grow very well, and were cultured using methods that are outdated. What's more, the chromosomes undergo subtle changes over time, compromising the cells' ability to remain "normal." Back in the late '90s, when the lines were created, "we didn't know much about growing stem cells," says Kevin Eggan, principal faculty member at the Harvard Stem Cell Institute. "They can't do what the newer cell lines can do." Curt Civin, a cancer researcher at Johns Hopkins, has spent the past several years trying to differentiate the presidential lines into blood cells that could be used to treat leukemias and other blood-based cancers. But the age and quality of the cells have been a constant hindrance. "We want to study normal cells," he says. "We're working with Version 1.0. I'd like Version 3.3."