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From the Chicago Tribune Embryonic clones tied to medical advances New research on stem cells stirs moral debate By Jeremy Manier and Peter Gorner Tribune staff reporters Originally published April 27, 2001, 9:08 AM EDT WASHINGTON -- Researchers on Thursday released evidence suggesting that a patient's own embryonic clone could be used as a source of stem cells to treat that person for Parkinson's disease, diabetes and an array of other ailments. Still theoretical, the technique -- called "therapeutic cloning" because it would create a cloned embryo not to reproduce a person but to heal him or her -- may become illegal before researchers can try it in humans. A bill introduced in Congress on Thursday would ban all human cloning, including therapeutic cloning, which one of the legislation's sponsors called "reprehensible" because it would entail creating a cloned embryo only to destroy it. The emerging controversy puts a new spin on the debate over cloning because many scientists who oppose reproductive cloning of humans support research on therapeutic cloning. But the debate pits researchers against religious conservatives on some of the same issues that have stalled other work on stem cells taken from embryos. Scientists prize such cells for their unique potential as replacement parts for diseased tissue. Opponents of the research contend that creating or harvesting human embryos for stem cells is tantamount to murder. The Bush administration last week delayed the first meeting of a committee charged with reviewing applications for government funding of embryonic stem cell research. Although President Bush has said he is opposed to such work, other officials such as Department of Health and Human Services Secretary Tommy Thompson have supported the research. Therapeutic cloning combines two of the most controversial research areas in science: embryonic stem cells and cloning. Proponents of the approach say they have no intention of making full- grown human clones. Rather, scientists would take stem cells from cloned embryos in the first 14 days after they are created, before they can grow beyond 100 cells. In a study published Friday in the journal Science, researchers from Rockefeller University and Memorial Sloan-Kettering Cancer Center in New York were able to extract stem cells from cloned mouse embryos. The stem cells grew into many different cell types, including a kind of neuron that is damaged in Parkinson's disease. In practice in humans, the method would involve laboratory researchers taking a cell from an ill person and placing DNA from the cell into an egg that has had its own genetic material removed -- thus producing an egg that would develop into a human clone if it were implanted in a uterus. But instead of placing the embryonic clone in a womb, technicians would grow it for a few days in a petri dish and then extract stem cells, which could be used to make brain cells, liver cells or some other kind of tissue the ill patient might need. Such techniques could yield replacement tissue that would be genetically identical to the person's own cells, virtually eliminating the risk of immune rejection. The new study is "the first step in showing this kind of therapy might work," said Dr. Lorenz Studer, co-author of the paper and a researcher at Sloan-Kettering. The stakes in the debate are high because of the tremendous promise stem-cell therapy holds for millions of patients with such degenerative conditions as Parkinson's and Alzheimer's diseases and multiple sclerosis. In another major report in the new issue of Science, researchers used stem cells from mice to create insulin-producing tissue an advance that could lead to revolutionary treatments for diabetes. "This is the first example of assembling a functional, multicellular organ from cells grown in the lab," said Ron McKay, chief of the laboratory of molecular biology at the National Institute of Neurological Disorders and Stroke. The possibility of developing such treatments through therapeutic cloning led British lawmakers in January to pass a law allowing therapeutic cloning so long as embryos are not allowed to develop beyond 14 days. Sen. Ben Nighthorse Campbell (R-Colo.) earlier this month proposed a ban on human reproductive cloning that left room for therapeutic cloning. The new legislation introduced Thursday would ban therapeutic cloning on moral grounds, said one of the bill's co-sponsors, Rep. Dave Weldon (R-Fla.). Therapeutic cloning is "creating for the purpose of killing," Weldon said in an interview. "I think it's a very morally hazardous road to go down." Yet that's far from the position of Rudolf Jaenisch, a cloning expert from the Massachusetts Institute of Technology who strongly opposes human reproductive cloning because animal studies suggest the technique can produce abnormal offspring. Jaenisch said that in contrast, therapeutic cloning research offers significant advances and should be allowed under the law. Jaenisch and other researchers argue that before the cloned embryo is implanted in a uterus and starts forming specialized tissues, it is essentially an undefined "ball of cells." "Is this a small person? Some people would probably believe it is," Jaenisch said. "I think the majority of scientists do not believe that." Similar arguments apply to embryonic stem cell research that does not involve cloning, Jaenisch said. Most such work, done with private funding, uses extra embryos originally created for in-vitro fertilization. Researchers said that promising new work using adult cells to produce stem cells could eliminate some of the reliance on embryos. The deep uncertainty about which approaches will prove best in the fast-moving field of stem cell research leads some experts to urge increased work on all fronts, including adult cells and therapeutic cloning. "We need multiple tracks, because one or the other might not pan out," said Ronald Green, director of the center for ethics at Dartmouth College. In an editorial in Friday's edition of Science, Nobel laureate David Baltimore, president of the California Institute of Technology, warns that a moratorium on embryo stem cell research and transplantation could be "devastating." Although work with adult stem cells is promising, it's still only a hope, Baltimore wrote, "and it would be foolish to abandon the surer path for the unproven one." If researchers in the U.S. do not move ahead on such work, he warned, advances may come from Britain and other nations where such work is permitted. Robert Lanza, vice president for research at Advanced Cell Technology Inc., which plans on pursuing therapeutic cloning in humans, said he believes other nations surely will move ahead with therapeutic cloning if the U.S. does not. "I would say at least one or two groups will report something within the next year," Lanza said. Copyright © 2001, The Chicago Tribune http://www.sunspot.net/news/nationworld/sns- stemcells.story?coll=sns%2Dnewsnation%2Dheadlines http://www.chicago.tribune.com/version1/article/0,1575,SAV- 0104270217,00.html ******* ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn