A single gene\'s effect on the brain can result in non-stop eating, research has shown. Scientists believe the \"gluttony gene\" may be responsible for cases of obesity caused by out-of-control appetite. The Bdnf gene variant, studied in mice, was found to stop brain neurons from transmitting signals telling the body it has eaten enough.\"This discovery may open up novel strategies to help the brain control body weight,\" said lead researcher Dr Baoki Xu, from Georgetown University in the US. The sensation of \"feeling full\" is governed by two hormones in particular, leptin and insulin. \"Short\" versions of the Bdnf gene block the leptin and insulin signals and prevent the \"stop eating\" message passing through the brain to the correct appetite-suppressing loc- ations, the scientists said.