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Crossing the Line in Baby-Making?

Family chooses embryo for ability to donate marrow


Updated May 05, 2004

Scientists have long hoped to use genetic testing to prevent and/or treat serious illnesses. In recent years, genetic testing has enabled couples to have children not only free of a particular hereditary disease but who are also perfect stem cell donor matches for older siblings with the disease.

Couple makes headlines with embryo selection
In 2000, Jack and Lisa Nash, of Englewood, Colorado, made headlines with their story of genetic selection. They have a daughter named Molly who was born with Fanconi anemia. Fanconi anemia is a rare congenital blood disorder that produces too few red blood cells, causing anemia; too few white cells, making the child susceptible to infection, and too few platelets, making it difficult for the blood to clot. Many children with Fanconi anemia develop leukemia (blood cancer) and die before age 10.

In 1998, Molly developed a "preleukemia" condition, and it became apparent that she would need a stem cell transplant in order to survive. If Molly received a transplant from an unrelated donor, the odds of success would be only 40 to 50 percent.

The Nashes met a blood transplant specialist who told them about a technique that used blood from a new baby's umbilical cord. The umbilical blood contains stem cells that can create new blood cells and boost the immune system. A sibling who matched Molly's blood type could offer an 85 percent success rate this way.

The Nashes were already trying in vitro fertilization (IVF) and genetic screening to choose an embryo that wouldn't have Fanconi anemia. Unfortunately, Lisa did not become pregnant. They decided to try again, and this time the doctors screened for both Fanconi anemia and for a blood match for Molly. An embryo was found, implanted, and on August 29, 2000, baby Adam was born.

Preimplantation genetic diagnosis
Genetic testing of embryos (called preimplantation genetic diagnosis, or PGD) is not new. Many families have selected healthy embryos this way. What is unique about the Nashes' case is their use of PGD to select an embryo as a tissue donor. As quoted by The New York Times, Dr. Jeffrey P. Kahn, director of the Center for Bioethics at the University of Minnesota, stated about the case, "We've crossed the line that we really never had crossed before, selecting based on characteristics that are not the best for the child being born, but for somebody else." Dr. Wagner stated that there are other families preparing to use the new procedure to select an embryo. The Nashes, being the first, sparked the controversy, but Lisa Nash felt it would be wrong to keep their situation a secret if it would help other families.

Molly gets stem cells from Adam
On September 26, 2000, Molly received a transfusion of Adam's umbilical cord and placental blood. The procedure involved no pain or risk for Adam, and other than the intravenous needle, little discomfort for Molly. At last report Molly's blood tests showed significant improvement in the numbers of blood cells she had.

Moral and ethical questions
There has been some public outcry that using GPD to select embryos this way will become a slippery slope, in that it will eventually lead to choosing embryos for things like high IQ or body characteristics. Others argue that we should use scientific knowledge and technology to save lives whenever possible. Another consideration is that the fertilized embryos which are not selected are stored, so perfectly healthy embryos could end up being discarded, which is common at fertility clinics.

Information for this article was taken from:
- Fischer, Joanne. A brotherly donation. U.S. News & World Report, October 16, 2000
- Grady, Denise. Baby conceived to provide cell transplant for his dying sister. The New York Times, October 4, 2000

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