A correlation between obesity and genetics has been found to be modified by diet, according to a scientific paper in the American Journal of Clinical Nutrition. A research group led by a U.S. Dept. of Agriculture (USDA) scientist found that a specific gene—APOA2—can result in a higher body mass index (BMI).
The APOA2 gene encodes a protein that is part of high-density lipoprotein (HDL) cholesterol, so-called “good” cholesterol. An epigenetic mark, which can be thought of as a type of natural chemical decoration on the genome that regulates gene activity, can be induced and modified by environmental factors, such as dietary intake and lifestyle habits.
Led by molecular biologist Chao-Qiang Lai from the USDA Agricultural Research Service’s (ARS) Nutrition and Genomics Laboratory at Tufts University, the study found the same epigenetic mark also is likely associated with greater appetite, and this can result in greater food consumption and a higher BMI. This study is the first of its kind to take such an in-depth examination of a gene-diet interaction, one that pertains to obesity and the differential response to dietary saturated fat between individuals carrying variants of a specific gene, APOA2.
The research group started with 80 individuals and then replicated their initial findings in two additional populations. The group’s analyses identified an epigenetic mark—a genetic feature not directly governed by the genetic code—that is associated with saturated fat intake exclusively in subjects who carry the APOA2 gene. According to Lai, these discoveries could explain why individuals with this genetic factor consume more food and have a higher BMI