Attacking Heart Disease at It's Genetic Base

Suppose we knew all the genes involved in cardiovascular healthwhich ones contribute to risk, which contribute to protection, and how much each contributes individually and in combination.

It may sound like a tall order, but that's exactly what researchers here and abroad are working toward. They want to be able to reduce a person's likelihood of cardiovascular disease based on his or her genetic profile, as well as on the individual's age, gender, and lifestyle habits.

It may sound like a tall order, but that's exactly what researchers here and abroad are working toward. They want to be able to reduce a person's likelihood of cardiovascular disease based on his or her genetic profile, as well as on the individual's age, gender, and lifestyle habits.

A genetic profile would enable individuals to adopt the habits most likely to reduce riskbecause different genes or gene combinations respond differently to changes in diet, exercise, smoking, alcohol consumption, or medications such as cholesterol-lowering drugs. And as more and more information becomes available, recommendations for change will become more reliable.

One of the pioneers in this field is Jose M. Ordovas, a biochemist at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, Massachusetts. He has identified several of the 40 or so genes so far known to affect cardiovascular health. He estimates that there may be hundreds of genes that will ultimately go into a risk-analysis database.

Ordovas explains that four main components under genetic control contribute to coronary artery disease risk, known as "syndrome x":

• high blood lipidstotal and LDL cholesterol, triglycerides;

• impaired glucose tolerance and diabetes;

• high blood pressure;

• obesity (in the abdomen).

Whether the genes for any of these components are manifest depends on an individual's habits as well as age, Ordovas says. Moreover, manifestation is interrelated.

For example, in an obese person, a gene for obesity can trigger a normally beneficial gene for blood lipids to express high LDL cholesterol and triglycerides. But if the person stays lean, the beneficial gene could prevailall other things being equal.

Someday, health professionals will have a fairly complete profile of the human genes involved in raising or lowering risk, says Ordovas. Children could be tested early in life so that diet and other lifestyle changes would be started before damage begins.

Sources:

By Judy McBride, Agricultural Research Service Information Staff.

This research is part of Human Nutrition Requirements, Food Composition, and Intake, an ARS National Program described on the World Wide Web at

is at the USDA Human Nutrition Research Center on Aging at Tufts University, 711 Washington St., Boston, MA 02111; phone , fax .

"Attacking Heart Disease at Its Genetic Base" was published in the July 1999 issue of Agricultural Research magazine.