African American Blood Pressure Study Identifies New Gene Variants

A new study detailing the largest-ever genetic analysis of blood pressure in African Americans has identified five gene variants linked to the trait. According to the study, which was published recently in the American Journal of Human Genetics, three of the gene variants have not previously been implicated in blood pressure, and represent novel findings.

“High blood pressure occurs in roughly 40 percent of African Americans, which is a much higher rate than in other U.S. ethnic groups, and adds a significant risk to the development of cardiovascular disease,” said one of the paper’s co-senior authors, Center for Applied Genomics (CAG) geneticist Brendan J. Keating, D. Phil. According to the CDC, roughly 1 in 3 American adults — approximately 67 million people — have high blood pressure. High blood pressure can lead to a number of serious health conditions, including kidney disease, stroke, and heart attacks and heart failure.

In the discovery portion of the American Journal of Human Genetics study, the researchers performed a meta-analysis of 19 different studies, comprising “data from nearly 30,000 African American individuals,” said Dr. Keating. In study’s replication phase, the researchers validated the findings in over 100,000 individuals of different ancestries. They discovered five gene variants associated with blood pressure.

Three of the variants discovered in the study had not previously been reported for blood pressure. Two other gene variants in those subjects had previously been discovered in patients of European ancestry. “These findings actually explain only a very small portion of the genetic variation that we know underpins blood pressure in individuals of African ancestry, so further independent studies need to be added to these efforts to discover even more variants,” said Dr. Keating.

This new research follows an April Nature Genetics study — to which Dr. Keating also contributed and which was led by CAG’s Struan Grant, PhD — that discovered new loci associated with body mass index in adults of African ancestry. Non-Hispanic blacks are 51 percent more likely than whites to be obese, according to the CDC.

While the new research findings do not have immediate implications for treatment, the hope is that discovering genes associated with disease risks will bring scientists closer to biological pathways and may suggest useful drug targets for new treatments.

“Gaining more biological knowledge of the factors underlying blood pressure levels will help us to obtain new insight into the development of hypertension and to identify potential new drug candidates for therapy,” Dr. Keating noted.