July 19, 2013
Researchers at Boston Children’s Hospital have identified a genetic cause of severe obesity that, though rare, raises new questions about weight gain and energy use in the general obese population. The research, published in the journal Science on July 19, involved genetic surveys of several groups of obese humans and experiments in mice.
Mice with the genetic mutation gained weight even while eating the same amount of food as their normal counterparts; the affected gene, Mrap2, has a human counterpart (MRAP2) and appears to be involved in regulating metabolism and food consumption.
“These mice aren’t burning the fat, they’re somehow holding onto it,” says the study’s lead investigator Joseph Majzoub, MD, chief of endocrinology at Boston Children’s. “Mice with the genetic mutation gained more weight, and we found similar mutations in a cohort of obese humans.”