Study Links Genes to Heart Disease

Tuesday, November 27th 2001, 12:00 am

By: News On 6

DALLAS (AP) _ Scientists say they have found evidence linking three genes to premature heart disease in what could be a step toward a better screening procedure for families at risk.

Using a new technique called high throughput microarray genotyping to sift through some 50,000 genes, the researchers found that three produce thrombospondin. The protein governs blood's ability to clot, a factor in heart disease.

The study in Tuesday's issue of the journal Circulation found that families with a variant of a gene called thrombospondin-4 were 89 percent more likely to have a premature heart attack compared with those who had a normal gene of the same type.

Researchers also found that a variant of the gene thrombospondin-1 was 10 times more likely to form blood clots, while a variant of another gene _ thrombospondin-2 _ actually reduced the risk of heart attack by 69 percent.

The study looked at 400 families at 15 medical centers across the United States.

Dr. Eric Topol, the study's author and a chairman of cardiovascular medicine at the Cleveland Clinic Foundation, said the study was just a first step in the quest to find the root causes of heart disease.

``The hunt for the genes to explain this disease has actually not gone too far yet,'' Topol said. ``We know there's something going on. Each of these variants are making very abnormal proteins.''

Topol said the research could lead to a screening procedure to identify at-risk families at an early age. He said the next step is for others to replicate his findings and show the cause-and-effect relationship between the suspect genes and heart illness.

Experts said the study suggested that researchers were on the right track.

``There are millions of segments of genes. This is just one segment,'' said Dr. David Fischman, a cardiologist and an assistant professor of medicine at the Thomas Jefferson Medical College in Philadelphia.

He said research is farther along on genetic markers that could predict cancer risks. Fischman predicted ethical battles over whether to manipulate genetic codes in an effort to stop diseases, citing controversy surrounding this week's claim by a Massachusetts company that it had cloned a human embryo.

``This (gene therapy to prevent heart attacks) won't raise as much as that, but it will probably raise considerable controversy,'' Fischman said.