New research out of the University of Texas MD Anderson Cancer Center indicates that African-Americans are genetically predisposed toward obesity. The study found that African-Americans shared 32 gene variants that have been previously found in obese individuals in Asian and European populations.
“In African-Americans, genes played a greater role in causing increased BMI (Body Mass Index) than in Caucasians,” said Professor Christopher Amos of the University of Texas. “To date, the effects in both African-American and Caucasian participants are too small to explain much of the genetic variability in obesity rates, and this may be because the variation reflects both genetic and environmental contributions. Since the environmental factors have not been studied, the actual contribution from genetic factors may be greatly underestimated.”
Naturally, environmental factors play into whether or not a person is obese, but finding genetic traits that incline a person toward obesity might give scientists clues as to how they can begin fighting obesity from a genetic level.
“I would love to stress that this paper is really just a start or a foundation for understanding the role of genetic variation in obesity,” said Professor and co-author of the paper Jason Moore from Dartmouth. “We expect obesity to be influenced by hundreds, if not thousands of genes and many, many environmental factors. While some genetic variants are likely to increase or decrease weight in all people, most are likely to influence weight in specific people depending on their genetic background and their unique environmental history including diet, toxic metal exposure, exercise, etc. We will not fully understand the genetics of obesity until we can fully investigate these context-dependent genetic effects.”
More than 50 percent of adult African-Americans are obese, versus 35 percent of non-Hispanic white adults. By finding the genetic markers that skew a person toward obesity, medicine might be capable of finding a way to help limit the number of obese adults, which would, in turn, help lower the levels of heart disease and diabetes in the population as a whole.
“This research has helped to illuminate human evolutionary history and serves to bring disease presentation into an evolutionary perspective,” concluded Professor Williams of Dartmouth.