A common gene variant found in 16 per cent of the population could be largely responsible for exploding rates of obesity, it has been claimed.
The obesity gene was identified by a population-wide screening study led by scientists from the Peninsula Medical School in Exeter and the University of Oxford.
DNA samples from more than 38,500 people from across Britain and Finland showed a strong association between a particular variation of a gene called FTO and obesity.
Genes come in pairs, and individuals carrying one copy of the FTO mutation were found to have a 30 per cent higher risk of being obese than those with no copies.
The increased risk rose to 67 per cent for people who had two copies of the gene variant. People with two copies of the gene are three kilograms heavier on average. About one in six white Europeans have both copies.
Obesity is defined by a Body Mass Index (BMI), a measurement relating weight and height, of 30 and over. People who are overweight have a BMI that is between 25 and 30.
The new findings are the first to identify a common, population-wide genetic link to obesity.
Experts hope the discovery will help them tackle rising levels of obesity, and the associated risk of type 2 diabetes. It might also point towards new drug treatments that stop people becoming grossly overweight.
PA