THURSDAY, Oct. 14, 2010 (HealthDay News) -- Genetics may help explain the increased risk for high blood pressure among people of African descent, according to U.S. researchers.
The study authors said a gene on chromosome 5 appears to influence the production of the sodium-regulating hormone aldosterone.
For this study, the researchers analyzed genetic data from families on the Caribbean island of Tobago (where the population has about 94 percent African ancestry) and found that genetics account for 34 percent of individual variations in plasma aldosterone concentration and about 25 percent of variation in systolic and diastolic blood pressure.
Levels of aldosterone tend to be high in people of African descent, the study authors noted.
"Aldosterone was very important to their early ancestors in the arid climate of Africa," study co-author J. Howard Pratt, of the Indiana University School of Medicine in Indianapolis, said in a news release from the American Heart Association (AHA). "Dietary intake of sodium in today's world is much higher, and there may not be the need for the amount of aldosterone produced, leading to a level of sodium balance that places individuals at risk for hypertension."
The study was to be presented Thursday at the AHA's Scientific Sessions on high blood pressure.
The U.S. National Heart, Lung, and Blood Institute has more about high blood pressure.