On a trip to Ireland a few years ago, I was struck by a number of faces among the crowds. They were children with the tell-tale look of Down syndrome.
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What struck me was the realization that I hardly ever see these young faces out on the street in the United States.
A fascinating probe by the Associated Press suggests the reason. Gene testing of parental carriers is leading to the birth of fewer and fewer children with inherited diseases in the United States. Other conditions such as Down syndrome, which uses prenatal testing of the fetus, are also apparently being screened out in greater numbers.
By encouraging genetic testing for potential parents of European background, fewer and fewer children in the U.S. are being born with cystic fibrosis. Aggressive programs to offer genetic testing to a subset of Jewish ancestry has, over the last decade, resulted in a situation in which only about a dozen new cases of fatal Tay-Sachs Disease occur each year in babies in the United States. Experts believe that wider testing of parents may produce in the years to come a sharp decline in the number of children born with sickle cell disease and Fragile X syndrome, a leading cause of cognitive impairment in boys.
Reducing the burden of disease is obviously a good thing. But genetic testing of parents, and, as is now happening with increasing frequency, embryos, raises some difficult ethical challenges as well.
In many cases, genetic testing of parents may discourage them from trying to have a child but, in situations where there is risk but not certainty, some parents will try to conceive. Then, aware of the risk, they pursue further prenatal testing, and end any pregnancy in which a fetus could be affected.
Destroying an embryo is obviously a difficult ethical and personal choice. Not as obvious are two other ethical challenges that more and more testing creates: The impact on those with genetic disabilities and their families and the likely expansion of genetic testing to more and more conditions in the years to come.
As some families with a Down syndrome child have noted, fewer kids with Down may mean fewer public programs, fewer resources in schools and for housing and less political clout. If some genetic diseases begin to fade away, will society’s willingness to provide support for the diminishing numbers of those born with such diseases fade as well? And are we headed to a time when parents who choose not to be genetically tested find themselves condemned as morally irresponsible parents?
There may be broad agreement that getting rid of a disease like Tay-Sachs, which produces a slow, miserable and inevitable death, usually by age 4, morally justifies aggressive genetic testing and even decisions to abort pregnancies where the fetus has the disease. But, could the same ethical consensus be brought to bear concerning conditions such as deafness or dwarfism, which also have a genetic component?
And what about using genetic testing on parents to pick out those at high risk for passing on conditions such as breast cancer, depression, Alzheimer’s or addiction — conditions that involve genetic risks but that may not appear until mid-life or later and for which therapies may well be found in the future?
And at the far extreme will companies be free to tout genetic testing of would-be parents simply to try and make matches that would result in a "better" baby?
As with many scientific advances, the good they do comes with some very hard dilemmas for you and me.
Arthur Caplan is director of the Center for Bioethics at the University of Pennsylvania.
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