Risky business.

The same type of genetic analysis that has led to a marker for Huntington's disease (SN: 11/12/83, p. 311) may someday enable doctors to pinpoint just who is at risk of heart disease, says Philippe Frossard of California biotechnology, Inc., in Bay View. He and his colleagues have already identified 24 genetic markers associated with atherosclerosis. But more work needs to be done before the strength of the association, and thus its predictive ability, will be known, he says.

No single factor--including obesity, smoking history, positive family history or levels of cholesterol, its carriers or constituents--can predict if any one individual is likely to die of heart disease. Knowing who is at special risk would enable countermeasures, such as lifestyle change or drug treatment, before the disease has progressed.

Frossard and his colleagues started their search for genetic markers in and around genes involved with lipd metabolism and transport. They used enzymes to break the genes, and compared the fragment lengths from people with hardening of the arteries of fragment lengths from people without it.

Some of the patients with genes indicating a high-risk group had normal cholesterol levels; this contradiction, says Frossard, may help explain why serum cholesterol levels are not 100 percent accurate in predicting heart disease risk. Several of the markers are actually "protective"--people with the markers wer less likely to have heart disease.

The initial study, in conjunction with Gerd Assmann of Muenster (West Germany) University Hospital, was done on the genes of 500 Germans being evaluated for atherosclerosis by coronary angiography. The California Biotechnology workers are beginning a study on 3,000 U.S. residents. "In about two years we should have a battery of markers that should be sufficient for prediction," Frossard says. He expects such a test to cost less than $50 per person.