Professor Ian Wilmut of the University of Edinburgh envisions a world where sick people could draw new life from younger, healthier clones of themselves. Mr. Wilmut became famous for cloning Dolly the Sheep and is now one of the most prominent embryonic stem-cell and human-cloning researchers.
Scientists at Harvard University announced last week that they had taken a small but hopeful step toward the type of medical treatment Mr. Wilmut envisions, but without the need to clone human beings. Mr. Wilmut acted unimpressed. He quickly noted that the Harvard research needed a lot of work before it would be medically useful.
"In the meantime, let us not waste time," Mr. Wilmut told reporters in London. "There are methods of deriving embryonic stem cells from cloned embryos that could be used to study and, in time, to treat human disease. Let's get on with this, for the sake of thousands of patients."
Scientists like those at Harvard are increasingly working on ways to circumvent the ethical tar pit of embryonic stem-cell research. But supporters of cloning for cures, like Mr. Wilmut, remain ambivalent about the possibility of curing disease without making or destroying embryos.
The Harvard team's vision closely resembled that of Mr. Wilmut and his supporters. They all would like to find a way to replace injured or diseased cells-like those in the spinal cord of a quadriplegic-with healthy cells bearing a patient's exact DNA. Embryonic stem cells are pluripotent, meaning they can become any cell in the body. Scientists theorize that, if transplanted into a patient, embryonic stem cells could grow into any type of healthy tissue needed to cure disease. If the cells had the patient's DNA, there would, in theory, be no risk of the body rejecting the cells the way it might reject a donated organ.
Mr. Wilmut proposes manufacturing cloned embryos, letting them develop in the lab for several days, then extracting their stem cells for treatments like the one described above. The Harvard team took a different approach. They reprogrammed an adult skin cell so it would behave like an embryonic stem cell. Their technique fused the skin cell with an existing embryonic stem cell from the group of cells that President Bush approved for federal funding in 2001.
The Harvard research emerged on the heels of another possible alternative to embryonic stem-cell research. William Hurlbut at Stanford University promotes a scientific technique called altered nuclear transfer (ANT) that, like cloning, transfers the nucleus of an adult cell into a human egg. But before the transfer, scientists alter the DNA of the nucleus so that it will immediately produce pluripotent stem cells without ever turning into an embryo.
ANT and the Harvard researchers have ethical dilemmas of their own. ANT uses human eggs, which could become a scientific commodity if the research became widespread. Although the Harvard team uses stem cells derived before the 2001 federal cutoff date, they still were harvested at the expense of an embryonic life.
But both proposals have the potential to meet the demand for pluripotent stem cells that share someone's DNA without using human cloning.
Despite that fact, many stem-cell advocates, including members of the Harvard research team, refuse to consider any research as a replacement for embryo-destroying science or cloning. A press release from the Harvard Stem Cell Institute stated: "The researchers caution, however, that . . . the promise of their work should not be seen as a reason to slow present research efforts."
Pro-stem-cell scientists and politicians have made similar remarks, extolling the promise of stem cells derived from cloned embryos and downplaying the alternatives.
Meanwhile, bioethicists are questioning their motives. "Why are we saying that we have to create embryos to get embryonic stem cells when there might be another way to gain the same thing?" said Barbara Quigley, executive director of the St. Louis Center for Bioethics and Culture. There appears to be more at stake than the potential for cures, she told WORLD, such as "science wanting to be able to conduct the kind of research it wants to do without moral constraints.
"There are other agendas besides just therapies from embryonic stem cells that are a part of this discussion in the background," she said.