Scientists at the University of Oxford have found a link between the FTO (fat mass and obesity associated) gene and increased body weight.

Back in 2007, scientists discovered that people with two copies of a variant within the FTO gene are on average 3kg heavier than those without it, affecting 16% of all Europeans.

“Convincing Proof that the FTO gene causes obesity” says lead researcher.

In the latest research, published in Nature Genetics this week, scientists bred mice with extra copies of the gene, which ate more and became fatter than normal mice. After 20 weeks female mice with two copies of the FTO gene were 22% heavier than normal and male mice were 10% heavier – although researchers did comment that the weight differences in humans were unlikely to be as large.

The next stage of research will focus on why the FTO gene causes obesity, for example, whether it increases appetite or alters messages from our fat stores.

Professor Frances Ashcroft of Oxford University commented: ‘We can now think about developing drugs that turn down the activity of the FTO gene as potential anti-obesity pills – that’s a long way off and there’s no certainty of success, but it’s an enticing prospect.’