Re: New Stem Cell Method Avoids Destroying Embryos
From: art fougner, md (evsono@pipeline.com)
Thu Aug 24 07:31:16 2006
I read that with great interest, Dean. I wonder if this will be
acceptable to DC.
Art
At Wed, 23 Aug 2006, Dean Huffman . wrote:
>
>..
>
>New Stem Cell Method Avoids Destroying Embryos
>
>NY Times
>
>http://www.nytimes.com/2006/08/23/science/23cnd-stem.html?ei=5094&en=50b7791f82ef2a9f&hp=&ex=1156392000&adxnnl=1&partner=homepage&adxnnlx=1156375437-P7AGwkonl=1&partner=homepage&adxnnlx=1156375437-P7AGwko3/science/23cnd-stem.html?ei=5094&en=50b7791f82ef2a9f&hp=&ex=1156392000&adxnnl=1&partner=homepage&adxnnlx=1156375437-P7AGwko+xaetpfMxegccug
>
>By NICHOLAS WADE
>
>Published: August 23, 2006
>
>Biologists have developed a technique for establishing colonies of human
>embryonic stem cells without destroying embryos, a method that, if confirmed in
>other laboratories, would seem to remove the principal objection to stem cell
>research.
>
>“There is no rational reason left to oppose this research,” said Dr. Robert
>Lanza, vice president of Advanced Cell Technology and leader of a team that
>reported the new method in an article in Thursday’s Nature.
>
>But critics of human embryonic stem cell research raised other objections,
>citing the possible risk to the embryo from using the technique, and the fact
>that it depends on in-vitro fertilization, the generation of embryos outside
>the womb from a couple’s egg and sperm.
>
>The new technique would be performed on an embryo when it is two days old, after
>the fertilized egg has divided into eight cells, known as blastomeres.
>
>In fertility clinics, where the embryo is available outside the mother in the
>normal course of in-vitro fertilization, one of these blastomeres can be
>removed for diagnostic tests, such as for Down’s syndrome, and the embryo, now
>with seven cells, can be implanted in the mother if no defect is found.
>
>Many such embryos have grown into apparently healthy babies over the ten years
>or so the diagnostic tests have been used.
>
>Up to now, human embryonic stem cells have been derived at a later stage of
>development when the embryo consists of about 150 cells. Harvesting these cells
>destroys the embryo.
>
>Last year, Dr. Lanza reported that embryonic stem cell cultures could be derived
>from the blastomeres of mice, a finding others have confirmed. He now says the
>same can be done with human blastomeres.
>
>Although he used discarded human embryos in his experiments, he said that anyone
>who wished to derive human embryonic stem cells without destroying an embryo
>could use a blastomere removed for the test, called pre-implantation genetic
>diagnosis or P.G.D. “By growing the biopsied cell overnight, the resulting
>cells could be used for both P.G.D. and the generation of stem cells without
>affecting the subsequent chances of having a child,” he said.
>
>Ronald M. Green, an ethicist at Dartmouth College and an adviser to Advanced
>Cell Technology, said he hoped the new method “provides a way of ending the
>impasse about federal funding for this research.”
>
>He said he believed the method should be seen as compatible with the
>Dickey-Wicker amendment, the Congressional action that blocked the use of
>federal funds for research in which a human embryo is destroyed or exposed to
>undue risk.
>
>Dr. James Battey, head of the stem cell task force at the National Institutes of
>Health, said it was not immediately clear if the new method would be compatible
>with the Congressional restriction, since removal of a blastomere subjects the
>embryo to some risk. But the embryos that are P.G.D.-tested seem to grow into
>babies as healthy as other babies born by in-vitro fertilization, Dr. Battey
>said.
>
>President Bush allowed federal funding for research on human embryonic stem
>cells, provided they were established before August 9, 2001. Although that
>might seem to rule out any new cell lines derived from blastomeres, Dr. Battey
>said it was not clear if that would be the case, since the embryo is not
>destroyed, and that he would seek guidance on the point.
>
>Critics, however, have a range of objections to the research. Catholic bishops,
>in particular, oppose both in-vitro fertilization and P.G.D. testing, and
>therefore still object to the research, even though the cells would be derived
>from an embryo that is brought to term.
>
>Richard Doerflinger, deputy director for pro-life activities at the United
>States Conference of Catholic Bishops, said the church opposed in-vitro
>fertilization because of the high death rate of embryos in fertility clinics
>and because separating procreation from the act of love made the embryo seem
>“more a product of manufacture than a gift.”
>
>Asked if he meant the parents of an in-vitro child would love it less, Mr.
>Doerflinger said he was referring to the clinic staff.
>
>“The technician does not love this child, has no personal connection with the
>child, and with every I.V.F. procedure he or she may get more and more used to
>the idea of the child as manufacture,” he said.
>
>Dr. Leon Kass, former chairman of the President’s Council on Bioethics, said, “I
>do not think that this is the sought-for, morally unproblematic and practically
>useful approach we need.” He said the long-term risk of P.G.D. testing is
>unknown, and that the present stem-cell technique is inefficient, requiring
>blastomeres from many embryos to generate each new cell line. It would be
>better to derive human stem cell lines from the body’s mature cells, he said, a
>method that researchers are still working on.
>
>Scientists welcomed the new development, but also expressed concerns. Dr. Irving
>Weissman, a stem cell expert at Stanford University, said the new method, if
>confined to P.G.D.-derived blastomeres, would not provide a highly desired type
>of cell, those derived from patients with a specific disease.
--
art fougner, md
"May The Wings of Liberty Never Lose a Feather." - Jack Burton
