Research Review

Sociocultural, Genetic Data Work to Reveal Health Disparities

When it comes to health disparities between different groups, how society sees people in terms of race might play a greater role than genetics, according to a University of Florida study. The study also showed that taking stock of sociocultural factors might improve our understanding of how genes influence individual health—regardless of race.

The study, published in the journal PLoS ONE, is the first to rigorously combine both sociocultural and genetic data to simultaneously test the relative contributions of each to racial inequalities in health.

“What’s really groundbreaking is that we’ve got both types of data and they’re of equivalent sophistication,” says coauthor Connie Mulligan, PhD, an associate professor of anthropology and an associate director of the UF Genetics Institute.

The results suggest that previously reported associations between genetic ancestry and health might be accounted for by sociocultural factors related to race and racism, and not necessarily to genetic differences between races. It also suggests that including sociocultural factors can strengthen genetics studies and help reveal how social inequalities can lead to biological differences.

In general, members of racial minorities in the United States suffer poorer health, and more die prematurely compared with their white counterparts. African Americans are three times more likely than whites to die from high blood pressure, according to the American Heart Association.

“The sheer scale of inequalities in sickness and death deserves our attention,” lead author Clarence C. Gravlee, PhD, an assistant professor of anthropology said. “Researchers have an obligation to explain the origins of these inequalities and to identify social factors that could be targeted for policy change.”

To examine the link between African ancestry and blood pressure, the team studied 87 adults in Puerto Rico, using two variables for which “race” is often used as a surrogate: genetic ancestry and social classification.

Genetic ancestry was assessed using gene variants that show large frequency differences among groups from different continents. Social classification was assessed by observers to estimate how people are perceived in everyday life in terms of skin pigmentation, or “color.” The researchers found that the three major “color” categories had overlapping genetic ancestry, and that there was a strong link between “color” and blood pressure, but not between genetic ancestry and blood pressure.

When only genetic ancestry was considered, no association was evident between candidate genes for hypertension and blood pressure. But when “color” and socio-economic status were included in the analysis, a significant association between the gene variant and blood pressure was uncovered.

“One of the important points here is that you can have an association between two biological variables like genetic ancestry and blood pressure, but it could be that the social and cultural implications of having African ancestry is what is driving this association,” Gravlee said.

— Source: University of Florida Health Science Center