Prescreening selects baby without the gene for early-onset of Alzheimer's.
The 33-year-old mother shows no signs of Alzheimer's. But she carries a genetic mutation called V717L linked to a familial form of the disease that starts as early as the mid- to late-30s (as opposed to the more common form of Alzheimer's which strikes late in life). Her father died of the condition at age 42, and 2 of her siblings also are carriers of the V717L gene. Her sister developed symptoms at age 38, quickly became unable to care for her children, and now lives in an assisted-living facility. Her brother showed evidence of cognitive decline at 35.
Desiring to have children who would never have to worry about developing early-onset Alzheimer's, the unnamed woman underwent 2 rounds of hormonal stimulation to increase egg production by her ovaries. Twenty-three eggs were retrieved and tested with preimplantation genetic diagnosis (PGF) to detect the V717L mutation. Eggs that were free of the mutant gene then were fertilized in a test tube with the husband's sperm. Four of the resultant embryos were implanted into the woman's uterus, and almost 18 months ago, she delivered a healthy baby, according to a report in the February 27 issue of the Journal of the American Medical Association.
PGF has been used to detect other genetic disorders, but this marks the first time it has been used to prevent the birth of a child with the V717L gene. The technique provides a "nontraditional option" for parents fearful of passing the gene on to their children, said lead author Yury Verlinsky, MD, director of the privately-funded Reproductive Genetics Institute in Chicago, IL.
Verlinsky and his associates pioneered PGF, a marriage of DNA testing and in vitro fertilization (IVF). In October 2000, the team created baby boy Adam Nash, who was genetically selected to provide an umbilical cord blood transplant for his older sister Molly, who suffered from Fanconi's anemia. Molly's life was saved, but some ethicists cautioned that genetic technology was being pushed too rapidly without full consideration of the moral issues and societal implications. This latest use of PGF has once again raised concerns over what should constitute ethically acceptable assisted reproduction.
In an accompanying editorial, Drs. Dena Towner and Roberta Springer-Loewy of the University of California-Davis agreed that the mother was acting ethically by preventing her child from having the genetic mutation. However, the "choice of bringing into the world a child for whom the mother will, with near certainty, be unable to provide care," raises ethical questions, they said.
Verlinksy believes the decision should be up to the patient, and said that the woman was a geneticist and well informed about the risks, including multiple gestations and misdiagnosis. He also noted that physicians can decide for themselves whether to engage in such work. For example, while some doctors offer PGD to select a baby's sex, Verlinsky said he is opposed to that use of the technology and does not offer the service.
Others reject the notion that embryo selection is a personal decision. "This is something that affects us all," said Jeffry Kahn, PhD, director of the Center for Bioethics at the University of Minnesota in Minneapolis. "It's a social decision. This really speaks to the need for larger policy discussions and regulation or some kind of oversight of assisted reproduction."
|Printer friendly Cite/link Email Feedback|
|Comment:||Prescreening selects baby without the gene for early-onset of Alzheimer's.|
|Article Type:||Brief Article|
|Date:||Mar 15, 2002|
|Previous Article:||Saudi transplant team performs world's first uterus transplant; lasted 99 days, produced 2 menstrual periods.|
|Next Article:||UK oks "designer baby;" more requests follow.|