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FROM: USA Today States dive into stem cell debates By Dan Vergano, USA TODAY Cloned babies. Embryo farms. Miracle cures. Shoot the TV if you want to avoid hearing the buzzwords of stem cell politics this year. In February, South Korean scientists announced that they had cloned the world's first mature embryonic stem cell line. You might want to aim for the radio, as well. An annual Senate debate has hit the road, moving to 33 state legislatures considering 100 bills that alternately condemn, condone or fund embryonic stem cell research. The legislative battles culminate in a California voter initiative in November that would, if approved, pump nearly $3 billion over 10 years into such research. "There is a tremendous amount of legislation flying around on one area of medical research. It is remarkable and unprecedented," says Dan Perry of the Coalition for the Advancement of Medical Research, a collaboration of 83 patient groups, universities and medical organizations that support the research. Why all the activity? Three years after President Bush severely limited federal spending on stem cell research, private institutions are figuring out ways to do end-runs. And onlookers in legislatures, on church councils and in the scientific community are raising a ruckus on all sides of the debate. Human embryonic stem cells are like blank slates. Early in a pregnancy, they turn into or, as scientists say, differentiate into all of the body's specialized tissues and organs. Since the University of Wisconsin's James Thomson first isolated and grew the cells in 1998, researchers have pondered how they might be used in medical treatments. If produced from cloned cells genetically identical to a recipient, embryonic stem cells could conceivably be grown into rejection-free transplant organs, although the technology does not yet exist to do so. Today, supporters such as the Juvenile Diabetes Research Foundation point to cloned cell transplants as a way to treat, and even cure, diseases such as juvenile (type 1) diabetes, cancer and Alzheimer's disease. Critics say the research is immoral because the cells are harvested from human embryos, most oftendiscarded ones donated by fertility clinics. The days-old embryos are destroyed in the process. -------------------------------------------------------------- Sidebar: Which cell to use: Adult or embryonic? In one side ring of the stem cell circus is the debate over adult stem cells vs. embryonic cells. Embryonic stem cells are found, obviously, in the embryo. They turn into every type of tissue, except placental ones. Cloned versions of these cells could potentially be turned into rejection-free transplant tissues capable of curing many diseases. Adult stem cells hide in adult tissues, serving as a repair system for the body. They are more specialized cells that give rise naturally to only a few kinds of tissues for example, bone marrow stem cells that regularly replenish blood cells. Those who oppose the destruction of embryos to harvest stem cells advocate the use of adult cells as a reasonable alternative. They note that unlike embryonic cells, adult stem cells have been used for more than 40 years in bone marrow transplants, and to treat inherited blood disorders and leukemia. Both types of stem cells are blank-slate cells without any function except to multiply and divide, becoming more specialized with each division, and turning into brain, blood, bone and every other type of tissue. Researchers are studying both types of cells to see whether they can be grown in the lab, coaxed into becoming needed types of tissues brain cells for Parkinson's patients for example and transplanted into patients. But in March, two studies in the journal Nature cast doubt on suggestions that adult cells are as capable as embryonic cells of becoming a wide variety of tissues. Some of the published, initial adult cell reports may have been too optimistic, and embryonic stem cells are still the "gold standard" for flexibilty, says prominent adult stem cell researcher Catherine Verfaillie of the University of Minnesota. For that reason, she and most researchers would prefer to study both kinds of cells. "The debate regarding whether adult stem cells or embryonic stem cells are 'better' is a creation of politics and the press, not of the scientific community," says stem cell scientist James Thomson of the University of Wisconsin in Madison. "I know of no credible stem cell scientist that does not believe that both should be studied; human medicine will suffer if either is excluded." ---------------------------------------- Opponents warn of a future in which the essence of being human is devalued, human eggs will become a commodity grown in "farms" and cloned babies will be commonplace. A bioethics standoff The satirical weekly The Onion mocked the debate in a story headlined "Potential Baldness Cure Leads Man To Reverse Position On Stem-Cell Research." But the bioethics issue has settled into a battle between an irresistible force and an immovable object: For the past five decades, utilitarian ethics have governed biomedical experiments. Bioethicist Art Caplan of the University of Pennsylvania summarizes the utilitarian position in the Feb. 20 Science magazine as "the moral argument that investing in science and technology extends life and improves the quality of life, despite exacting a toll in harms and risks." For that reason, researchers widely view experiments on embryonic cells as permissible because of their potential value in the search for cures and in expanding knowledge of human development. On the other side are views that suggest "moral tradition does urge us to treat each and every living member of the human species, including the early embryo, as a human person with fundamental rights, the first of which is the right to life," in the words of Richard Doerflinger of the U.S. Conference of Catholic Bishops. For that reason, research opponents consider the destruction of embryos for stem cells to be murder. Events this year have only intensified disagreement over the federal policy. In August 2001, Bush restricted funding to research involving stem cell lines already created. A stem cell line is a family of constantly dividing cells, the product of a single embryo. Of the more than 60 such lines then said to be available, only 18 actually ended up for use, for a fee, by researchers on a National Institutes of Health registry. "Many in the research community believe that the federal restrictions on funding of human embryo research create a chilling effect on embryo research generally," says the President's Council on Bioethics in its March report entitled "Reproduction and Responsibility." That chill has driven private institutes to take the lead. Nationwide there are eight such institutes, both at universities and in private firms. On Friday, the University of Wisconsin announced the founding of a 150-person stem cell research institute. And Harvard is expected to announce a $100 million stem cell research initiative this week. Overseas, a privately financed South Korean team announced in February the first embryonic stem cell line made from a cloned embryo. Creating such a line is a first step in turning cloned cells into rejection-free transplant tissues. And last month, a team led by biologist Doug Melton, a Howard Hughes Medical Institute researcher at Harvard, nearly matched the NIH registry in one fell swoop. In a New England Journal of Medicine report, Melton announced the creation of 17 embryonic stem cell lines available to researchers for free. In one month, the 320 requests for his cells exceed the roughly 300 filled requests for the stem cells on the NIH registry since 2001. University of Minnesota researchers say they will collaborate next year on an effort to test the use of embryonic stem cells as a medical treatment. Adding to the politicization of the debate, former President's Council member Elizabeth Blackburn, a cell biologist at the University of California-San Francisco, says she was ejected from the group in February because her support for such research clashes with the views of its chairman, American Enterprise Institute fellow Leon Kass. Kass is the bioethicist credited with crafting the Bush stem cell policy. Meanwhile, Sen. Sam Brownback, R-Kan., complains that the council "tragically" supported some embryo research in its March report by calling for a ban only on the use of embryos beyond 10 to 14 days of their development. That's much later than they are actually used in research. Brownback regularly sponsors legislation to ban embryonic stem cell research and says he will do so again this year. And so the debate continues. At the same time, a federal ban on cloning embryos to make babies has stalled in the Senate, even though a ban is supported by nearly everyone involved in the debate, from the American Society for Reproductive Medicine to the President's Council. Opponents cannot even agree on terminology. Brownback believes all cloning is reproductive, his aides say. Research supporters suggest therapeutic cloning, in which harvested stem cells are transplanted into a patient, involves research embryos that would never produce cloned children. A 'crazy quilt' of laws Research advocate Perry worries that the legislative activity in various states will lead to a "crazy-quilt" pattern of laws that will drive some scientists to states that support the research. The point has been made that Michigan State University biologist Jose Cibelli, a collaborator with the South Korean cloning team, would have faced a $1 million fine and 10 years in jail if he had conducted such research in Michigan. If politics were not involved, "the field of embryonic stem cell research would be much more advanced than it is today," research pioneer Thomson says. "It is difficult to estimate just how damaging the current restrictions have been to the field to date, but if the current restrictions are not eventually lifted, patients will suffer needlessly." For now, researchers don't know what signals coax stem cells to grow into specific tissues, says Catherine Verfaillie of the University of Minnesota Stem Cell Institute. "The cells tend to decide for us, and we have relatively little insight in how to control things. "Some combination of genetic analysis with stem cell experiments will have to occur to tease out those signals." And despite all the debate, embryonic stem cells may end up offering insight that is more scientific than therapeutic, Thomson says. "The real lasting contribution of human embryonic stem cell research may be increased knowledge of the human body, which could change human medicine even more dramatically than new transplantation therapies." Find this article at: http://www.usatoday.com/news/health/2004-04-20-stem-cell-cover_x.htm ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn