A SINGLE "gluttony gene" can cause non-stop eating and possibly obesity, research has shown.

The Bdnf gene variant was studied in mice. It was found to stop brain neurons sending signals telling the body it had eaten enough.

"This discovery may open up novel strategies to help the brain control body weight," said researcher Dr Baoki Xu, from Georgetown University Medical Centre in the US.

Hunger and satiety, or "feeling full", are governed by a mix of hormonal and neuronal signals.

The hormones leptin and insulin, released in the body after a meal, activate the hypothalamus region of the brain that trigger satiety.

But if the connection is not made, the food craving continues. "Short" versions of the Bdnf gene block the leptin and insulin signals.

The research is reported online in the journal Nature Medicine.