Stem Cell

NYT reported In a development that may shift the political debate over embryonic stem cells, researchers have devised two new techniques designed to alleviate ethical concerns.

Both are ridiculous.

In one, the cells are derived without the need to destroy an embryo, the principal objection of abortion opponents who have strenuously opposed federal financing of the research. The other technique makes skin cells revert to the embryonic state in a way that prevents the embryo from implanting in the uterus. Both are described in today's online edition of Nature.

The technique for making embryonic stem cells without compromising the embryo was developed in mice and has yet to be adapted to humans, but the two species are very similar at this level of embryonic development. "I can't think of a reason why the technique would not theoretically work" in people, said Brigid M. Hogan, an embryologist at Duke University. If it does work in people, the technique could divide the pro-life movement into those who accept or reject in vitro fertilization,

That is the whole reason for these foolish ideas, to try to divide the pro-life movement.

because the objection to deriving human embryonic stem cells would come to rest on creating the embryos in the first place, not on their destruction. "This gets around all of the ethical arguments except for that small minority of the pro-life community that doesn't even support in vitro fertilization," said Representative Roscoe G. Bartlett, Republican of Maryland, whose Web site describes him as "a pro-life legislator."

Sometimes web sites lie, but if he really understood what you propose, and still approves it, he is certainly not pro-life. He may know he has to say he is pro-life to get elected, but

Until now, the only way of deriving human embryonic stem cells has been to break open the embryo before it implants in the uterus, a stage at which it is called a blastocyst, and take out the inner cell mass, whose cells will form all the tissues of the future infant.

And thus kill the baby in a very early stage.

Although the blastocysts used in the procedure are ones that fertility clinics have rejected for implantation, opponents of abortion say destruction of any embryo is wrong. Congress has forbidden the use of federal funds for any such research, and federally supported scientists can work with only a small number of existing lines of embryonic stem cells that have been exempted from this stricture by President Bush.

Robert Lanza and colleagues at Advanced Cell Technology, a biotechnology company in Worcester, Mass., have now developed an alternative way of generating embryonic stem cells that leaves the embryo viable. At the eight-cell stage, reached by a fertilized mouse egg after its third division and just before the blastocyst is formed, they removed one cell. They then coaxed that cell, known as a blastomere, into growing in glassware and forming cells that have all the same essential properties as embryonic stem cells derived from the inner cell mass, Dr. Lanza's team reported. The seven-cell embryo was implanted in the mouse uterus and grew successfully to term. That part of the procedure is known to work with humans too, because it is the basis of a well-established test known as pre-implantation genetic diagnosis. In the test, one cell is removed from each of a set of embryos and tested for any of 150 genetic defects, giving the parents the choice of implanting an embryo that is disease free.

So you take a frozen embryo, let it start growing, then steal one cell and let it keep growing and because the resulting embryo will create a life you think the pro-life people will be convinced it is a good idea. But realize, that frozen embryo was not intended to be planted. Do you think that just because a baby is created that will live, even if it was unwanted, and even if some woman allows it to be implanted in her, and carried to term, that everything is ok? Or do you plan to steal a cell from embryos created for a woman that wants IVF, and will you tell her what you are doing?

Dr. Lanza's technique is likely to be welcomed by many in the middle of the debate, although it has not won over the United States Conference of Catholic Bishops. Richard M. Doerflinger, its deputy director for pro-life activities, dismissed the technique, saying that pre-implantation genetic diagnosis itself is unethical. The technique "is done chiefly to select out genetically imperfect embryos for discarding, and poses unknown risks of future harm even to the child allowed to be born," he said in an e-mail message.

I can't imagine anyone on the pro-life side who would approve.

Only a procedure that generated embryonic stem cells without creating or destroying embryos "would address the Catholic Church's most fundamental moral objection to embryonic stem cell research as now pursued," Mr. Doerflinger said in testimony last December to the President's Council on Bioethics.

Such as one that used adult stem cells.

.... In response to Dr. Grompe's reservation, Dr. Lanza said that individual human blastomeres had never been shown to create viable embryos. The reason is that by the eight-cell stage, each blastomere is probably committed to becoming either the outer shell of the blastocyst, which later forms the placenta, or the inner cell mass, which forms the fetus. Only the fertilized egg and the two-cell and perhaps four-cell stages retain the ability to form all the placental and embryonic tissues, Dr. Lanza said.

If Dr. Lanza's technique proved to work in humans, it could do more than just provide researchers with a new source of cells. It might allow every child born through pre-implantation genetic testing to have its own line of embryonic cells banked for the future. The blastomere removed at the eight-cell stage could be allowed to divide, with one cell being used for genetic testing and the other for growing a culture of perfectly matching embryonic stem cells. The cells would be available throughout the child's lifetime for the kind of tissue and organ repair that it is hoped stem cells will one day provide.

That has even more ethical problems.

With the parents' consent, those cells could also be used for research, providing many new embryonic stem cell lines for laboratories. The procedure might be even be offered for all embryos generated in fertility clinics when its theoretical risk has been better assessed. "I can see a day when every fertility clinic embryo has a cell removed and banked for future tissue use or organ replacement," Ronald M. Green, an ethicist at Dartmouth College, said.

I have had nightmares myself, but I never told them to a reporter for the New York Times

Children born after the pre-implantation diagnosis procedure have the same incidence of birth defects as ordinary children. So far, after some 10 years of experience, there is no indication that it causes health problems in humans, said Andrew R. La Barbera, scientific director of the American Society for Reproductive Medicine. If Dr. Lanza's technique succeeds in generating human embryonic stem cell lines, Dr. La Barbera said, "I suspect that indeed it will become routine to generate stem cells for everyone who undergoes pre-implantation genetic diagnosis."

I see a need for a new law.

But Kathy Hudson, director of the Genetics and Public Policy Center at Johns Hopkins University in Baltimore, said there was "little data that documents the safety and efficacy" of the pre-implantation diagnosis procedure, even after 2,000 births. She urged the American Society for Reproductive Medicine to create a national database to address the safety issue.

Second methodThe other alternative method reported in Nature today addresses an ethical objection to therapeutic cloning, the idea of treating patients with new tissues generated from their own cells. The cells would be obtained by taking the nucleus from a patient's skin cell and injecting it into a human egg whose own nucleus had been removed. The egg develops into a blastocyst from which embryonic stem cells can be derived in the usual way. Critics object that this nuclear transfer technique creates embryos only to destroy them.

A reasonable objection.

To counter this objection, Alexander Meissner and Rudolf Jaenisch of the Whitehead Institute in Cambridge, Mass., have created mouse nuclear transfer embryos that are inherently incapable of implanting in the uterus. They did so by switching off a gene in the donor nucleus that is needed for the implantation process. The gene was switched back on later because it is needed to form the intestinal tissues. William Hurlbut, a member of the President's Council on Bioethics, has suggested that such unimplantable embryos may satisfy those who say a potential life is being destroyed in the nuclear transfer process.

That is the most obscene thing I have heard of. They really don't understand our objection, do they?

But Mr. Doerflinger, of the bishops conference, told the Council last December that that approach did not fulfill the criterion that an embryo should not be created. That is still his position, he says. It is not yet clear if human embryonic stem cells generated from blastomeres would be eligible for federal financial support, since they might still fall foul of the Dickey-Wicker amendment

I certainly hope they would not be allowed.

by which Congress has prohibited federal research in which human embryos are destroyed, discarded or subjected to substantial risk.