Researchers Uncover Genetic Variants Linked To Blood Pressure In African-Americans

Main Category: Hypertension
Also Included In: Genetics
Article Date: 19 Jul 2009 - 0:00 PDT

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A team led by researchers from the National Institutes of Health reports the discovery of five genetic variants related to blood pressure in African-Americans, findings that may provide new clues for treating and preventing hypertension. The findings are published July 17 in the open-access journal PLoS Genetics.

Hypertension, or chronic high blood pressure, underlies an array of life-threatening conditions, including heart disease, stroke and kidney disease, and affects about one third of adults in the U.S. The burden is considerably greater in the African-American community, in which the condition affects 39 percent of men and 43 percent of women. Diet, physical activity and obesity all contribute to risk of hypertension, but research suggests that genetics also plays an important role.

Researchers analyzed DNA samples from 1,017 participants in the Howard University Family Study, a multigenerational study of families from the Washington, D.C., metropolitan area who identified themselves as African-American. Half of the volunteers had hypertension and half did not. To see if there were any genetic differences between the two groups, researchers scanned the volunteers' DNA, analyzing more than 800,000 genetic markers called single-nucleotide polymorphisms (SNPs).

The researchers found five genetic variants significantly more often in people with hypertension than in those without the condition. The variants were associated with high systolic blood pressure, but not with diastolic blood pressure or combined systolic/diastolic blood pressure. All five genetic variants were located in or near genes that code for proteins thought to be biologically important in hypertension and blood pressure. An existing class of anti-hypertension drugs, called calcium channel blockers, already targets one of the genes, CACNA1H. However, the additional genes may point to new avenues for treatment and prevention.

"This study is believed to be the first genome-wide association study for hypertension and blood pressure solely focused on a population with majority African ancestry," said the study's senior author, Charles Rotimi. "Although the effect of each individual genetic variant was modest, our findings extend the scope of what is known generally about the genetics of human hypertension."

"This work underscores the value of using genomic tools to untangle the complex genetic factors that influence the risk for hypertension and other common diseases," said Eric Green, scientific director for the National Human Genome Research Institute (NHGRI). "We hope these findings eventually will translate into better ways of helping the millions of African-Americans at risk for hypertension, as well as improved treatment options for other populations."

Financial Disclosure: This study was supported by the NHGRI, CRGGH, and the National Institute of General Medical Sciences, all part of NIH; and by the Coriell Institute for Medical Research. The Howard University General Clinical Research Center carried out the enrollment of study participants.

Competing Interests: The authors have declared that no competing interests exist.

Citation:
"A Genome-Wide Association Study of Hypertension and Blood Pressure in African Americans."
Adeyemo A, Gerry N, Chen G, Herbert A, Doumatey A, et al. (2009)
PLoS Genet 5(7): e1000564. doi:10.1371/journal.pgen.1000564

Source
National Institutes of Health