With fresh discoveries of disease genes announced almost weekly, more and more doctors are offering parents the possibility of having an abortion to prevent affected children from being born. However, an article in the Journal of the American Medical Association questions whether screening is appropriate for treatable or non-fatal diseases. Researchers in Israel who studied Gaucher disease, a condition whose symptoms range from severe to unnoticeable, found that 25% of couples aborted babies with the bad gene even though the abnormality would not have resulted in a serious health problem.

"Not until clinicians and researchers better understand the factors that determine whether a patient... will develop severe disease or none at all will screening for Gaucher disease become useful," said Dr Ernest Beutler, an expert on the condition. Until then, he said, such screening "will likely do more harm than good."

And ethicist Dr Lainie Friedman Ross, of the University of Chicago, said that the purpose of screening was not to test for minor diseases. "We want testing to help us diagnose a serious disease, to find the right treatments for those diseases -- treatments we'll respond to -- and some want it for making decisions about serious genetic abnormalities in their potential children," she said. "Gaucher doesn't fit into any of those models."