Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: THURSDAY, April 19, 1990 TAG: 9004190316
SECTION: NATIONAL/INTERNATIONAL PAGE: A11 EDITION: METRO
SOURCE: Associated Press
DATELINE: NEW YORK LENGTH: Medium
Further research might provide a way to screen out embryos that would develop serious genetic diseases, removing the prospect of abortions in those cases, researchers said.
The study was aimed at producing female babies in cases where a male could inherit a serious genetic disease, said researcher Alan Handyside. While the technique also would allow choosing the sex of a child without any medical reason, Handyside said he would consider that unethical.
The new work is reported in today's issue of the British journal Nature by Handyside and colleagues at the Royal Postgraduate Medical School at Hammersmith Hospital in London.
Laboratory techniques have been used before to determine a baby's sex. In 1986, a New Orleans fertility institute announced the birth of a boy whose sex had been selected during "in vitro" fertilization, which is done in the laboratory. That case involved selecting sperm to produce a boy.
But sperm selection has not proved reliable, said Dr. Maria Bustillo of the Genetics and IVF Institute in Fairfax, Va. And it does not hold the promise of diagnosing genetic diseases before an embryo is implanted, as embryo analysis does, she said.
It is not clear how many couples would choose the embryo analysis, which currently requires in vitro fertilization, rather than conceiving naturally and possibly considering an abortion after having a standard genetic analysis of the fetus, she said. But it may be possible someday to allow a woman to conceive naturally and then flush out the embryo for analysis, she said.
About 200 genetic diseases that typically affect only boys have been identified, including the most severe form of muscular dystrophy, hemophilia and a form of mental retardation, Handyside said.
The embryo analysis involves collecting eggs from a woman, fertilizing them in a test tube and letting them grow to eight-cell embryos. A single cell is removed from each embryo to see if it contains a bit of genetic material that indicates the presence of a Y chromosome, which would mean the embryo is destined to become a boy.
For families that risk passing on serious genetic disease to males, the embryo procedure should be less emotionally trying than an abortion, said Dr. Kathleen Nolan, a pediatrician and ethicist at the Hastings Center in Briarcliff Manor.
But she and ethicist Arthur Caplan at the University of Minnesota said thorny issues could arise if researchers find an easier way to analyze genetic traits of an embryo and as scientists learn to predict a variety of diseases and personal traits.
The issues essentially involve what diseases or traits might become grounds for preventing the birth of a child. Possible examples include conditions for which only a risk rather than a certainty can be predicted, diseases that appear only after decades of normal life and childhood diseases with which people can live into early adulthood.
by CNB