Researchers report on how a gene could influence some people to overeat and become obese.

Eating behavior is complex, and not completely understood, but when the genes that control it are defective, a person may not know when to stop eating. Understanding these genes may lead to new treatments for obesity, which has now become a serious public health issue.

A team at Imperial College of Science, Technology and Medicine in London, together with colleagues in the USA and France, now reveals the importance of the appetite stimulating gene GAD2. The work suggests that one variant of this gene may cause people to overeat by over-stimulating the appetite circuit in the brain.

They looked at the genetic make-up of 576 obese and 646 normal weight adults in France, from which they found two variants of GAD2. One of these was protective against obesity, the other was associated with it. The normal weight group had a higher frequency of the protective form of GAD2. Might this explain why obesity is three to five times less prevalent in France than in the USA? The study also revealed that those who carried the variant of GAD2 that is linked to obesity felt less able to control their eating.

Source

Public Library of Science Biology 2nd November 2003