EndocrinologyResearchers Uncover Genetic Variants Linked To Blood Pressure In African-Americans
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
National Institutes of Health