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-- [ From: Seymour Gross * EMC.Ver #2.5.3 ] -- New York Times, p.31 November 15, 1998 Clinton Asks Study of Bid to Form Part-Human, Part-Cow Cells By NICHOLAS WADE Saying that he is "deeply troubled" by the creation of part-human, part- cow embryonic stem cells, President Clinton has directed the National Bioethics Advisory Commission to consider the implications of the research at its meeting Tuesday in Miami and to report back to him "as soon as possible". In a letter sent Saturday to the chairman of the commission, Harold Shapiro of Princeton University, Clinton also asked for a review of embryonic stem-cell research in general, including the all-human embryonic stem cells whose isolation was reported earlier this month. These cells -- the primordial, all-purpose cells from which all tissues of the body develop -- were derived from very early embryos or blastocysts and from tissues of aborted fetuses. While the president signaled concern about the "mingling of human and non-human species," he was more positive about the all-human embryonic stem cell research, noting that it "may have real potential for treating such devastating illnesses as cancer, heart disease, diabetes and Parkinson's disease." But he also stressed the ethical concerns raised by the research, telling the commission that he wanted a "thorough review, balancing all ethical and medical considerations." The letter was sent after the president had consulted with the White House Domestic Policy Council and the president's science adviser, Neal Lane, "because he wanted the broadest views possible -- the policy people, medical ethicists, as well as the scientists," an administration official said. A political issue that lies in the background of the commission's deliberations is the ban on federal financing of fetal research. The ban , imposed by Congress, has created the situation that university scientists, who mostly depend on federal money, cannot work on the human embryonic stem cells whereas the private sector may conduct whatever research it pleases. A group of scientists and ethicists known as the Human Embryo Research Panel said in 1994 that research on human embryonic stem cells should be federally financed, provided that the cells were derived from excess pre -implantation embryos created for infertility treatments. This was the source of some of the human embryonic stem cells isolated earlier this month. In response to the panel's report, Clinton said in December 1994, "I do not believe that federal funds should be used to support the creation of human embryos for research purposes." The statement did not rule out research on excess embryos created in infertility clinics but subsequent action by Congress banned all research in which a human embryo is destroyed. Referring to this history, the president said in his letter Saturday that the ethical issues of human embryonic stem cell research had not diminished since his statement of 1994 but that the benefits had become less hypothetical. Lane said the implications of human embryonic stem-cell research had been under review but news of the human-cow hybrid cells, reported last week, "clearly raised urgent ethical, medical and legal issues that the president wants addressed and that's why he asked for the commission to give it immediate attention." Human embryonic stem cells can develop into any of the body's 210 types of cells, a process that happens naturally during fetal development. Biologists at Geron, the company that supported the research, hope to grow the cells in the laboratory and guide them to develop into heart cells, blood cells and other tissues. The cells would then be injected into the patient and integrate with tissues under the control of local body signals. In principle, the method could address a range of otherwise untreatable degenerative diseases, as well as relieving the severe shortage of organs available for conventional transplants. Many serious technical problems remain to be resolved, including finding ways to guide the stem cells down desired paths of development and ways to prevent immune rejection. The ethical problems are also important because of the source of the embryonic stem cells. In one case the cells came from excess pre- implantation embryos created in infertility treatments, and in the other from aborted fetal tissue. Both sources were legal, but research using the first would have been ineligible for federal money. The human-cow hybrid cell also complied with all laws, said Michael West , chief executive of Advanced Cell Technology of Worcester, Mass., the company that supported the research. In the hybrid cell, the cow cell's nucleus is first removed and the cow proteins are expected to be rapidly replaced with human proteins as the human nucleus takes over the cell. Although the mingling of species raises many questions, scientists at Advanced Cell Technology regard the operation as one in which the cow egg is used simply to make the human cell's nucleus revert to its embryonic state. As the human cells can be provided by the patient himself, from blood or skin, there is no immune rejection when developed cells grown from his embryonic state cells are injected back into the body. Advanced Cell Technology performed its cow-human hybrid experiment only once, three years ago, and took the study only to a very preliminary stage. Other scientists say more evidence is needed to verify whether embryonic stem-like cells were created. West said he was announcing the research now to test its public acceptability before making further investments in the technique.