Researchers use genomics to better understand blood pressure
Scientists at the National Institutes of Health are linking genetics to the risk of high blood pressure among black patients by analyzing genomic research databases.
The scientists believe variants in a gene known as ARMC5 may be associated with higher blood pressure among blacks, following a study that found 17 variants in the ARMC5 gene that were associated with high blood pressure.
However, researchers also found one variant gene that appears to be protective and associated with a role in regulating blood pressure and seems to be limited to people of African descent, but more study is needed.
“High blood pressure increases a person’s risk for heart disease and stroke,” says Constantine Stratakis, MD, scientific director at the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). “The condition is more common among blacks, who also tend to get it at a younger age than whites do, and we are studying the underlying causes of this health disparity.”
Use of information technologies to support multiple large genomic research databases, including access to human genome research databases, are helping scientists collaborate in the United States and United Kingdom. For example, work on the new variant gene also may suggest a new predisposition to tumor formation also in blacks with high blood pressure. “Until now, we knew nothing about the new variant gene,” Stratakis says.
Earlier work by the Eunice Kennedy Shriver National Institute of Child Health and Human Development group linked some variants of ARMC5 to primary aldosteronism, a hormonal disorder that causes high blood pressure among black patients.
In a newer study, analyzed datasets containing genomic information from large numbers of people were accessed via existing databases from the National Institutes of Health’s Minority Health Genomics and Translational Research Bio-Repository Database, and the Genomics, Environmental Factors and Social Determinants of Cardiovascular Disease in African-Americans Study in the United States, as well as from the United Kingdom Biobank.
The UK biobank is being used as another large dataset to confirm some results based on data from 3,000 people, and the researchers found the same results in both nations.
For now, the exact function of the ARMC5 gene is unclear, and more work is needed to understand what the gene does and how variants may protect or predispose a person to high blood pressure.
Today, researchers cannot definitively say there is a link between high blood pressure in black persons and the presence of a tumor, but the new gene does play a role in formation of tumors in the adrenal gland, Stratakis explains.
The new gene regulates early adrenal growth and likely affects how cells in adrenal glands proliferate and die. So now, researchers are looking for an on-off switch that may or may not affect blood pressure and tumors.
“Collectively, our research suggests that ARMC5 may play an important role in regulating blood pressure in blacks,” concludes Mihail Zilbermint, MD, and one of the lead authors of the study. “Because the gene is linked to primary aldosteronism (high blood pressure), ARMC5 may be involved in how the adrenal glands function with the hormones that are important for regulating blood pressure.”