New Findings on Genes, Hypertension Highlight Importance of Studying Populations with African Ancestry

May 17, 2017

A recent study at the University of North Carolina at Chapel Hill identified three novel genomic regions related to hypertension susceptibility in individuals with African ancestry.

While individuals of African descent suffer a disproportionate burden of hypertension and its complications, they historically have been underrepresented in genetic studies. This new finding underscores the importance of including African-ancestry populations as well as populations of European descent when studying biologic factors related to blood pressure.

The research team conducted a genome-wide association study of blood pressure in 31,968 Africans and African-Americans to identify genes that confer susceptibility to increased blood pressure. They found three genomic regions associated with blood pressure that had not been reported in previous studies of other races and ethnicities. Using experimental models, the researchers then demonstrated that the genes altered their expression in the kidney in situations related to hypertension.

Nora Franceschini, research associate professor of epidemiology, and Jianwen Cai, Cary C. Boshamer Distinguished Professor and interim chair of biostatistics, are researchers at the UNC Gillings School of Global Public Health and co-authors of the study. The full article on their findings, titled “Single-trait and multi-trait genome-wide association analyses identify novel loci for blood pressure in African-ancestry populations,” was published online May 12 by the journal PLOS Genetics.

“The unique genetic variation in populations of African ancestry provides important gains in gene discovery and fine-mapping of genomic regions associated with hypertension,” Franceschini explained. “Increasing the sample of participants in studies of European ancestry (which is the most common way to find genes) would not have helped to find these variants because they are rare or simply not present in European populations.”

High blood pressure is a leading global cause of disease, mortality and disability. Identifying genes with potential roles in human susceptibility to hypertension may lead to novel cures. As these findings show, however, it is crucial that public health researchers consider people of all ethnic backgrounds when studying biologic factors contributing to illness.