Genetic link to fat found
Updated on 12 April 2007
"I've got a slow metabolism" - it was the classic excuse for carrying excess weight. But could it actually have a basis in fact?
It's the most compelling evidence yet of a link between obesity and our genes.
Scientists in Exeter and Oxford have identified a single, common gene which makes its carriers up to 70 per cent more likely to be overweight.
The research, sponsored by the Wellcome Trust could even point the way towards a new drug treatment for the severely obese.
Slim is sexy, pigging out is shameful and that's got a lot to do with why dieting is a multi-multi million pound industry.
Unless it's calculated and calorie controlled, they say it's a moment on the lips a lifetime on the hips.
Or is it?
A huge new study has found the first conclusive link between weight and our genes. Could the fact that genes alone can make you 70 per cent more likely to be obese spell the death of the diet?
You're the one for me fatty
There's one big piece of evidence to suggest non-genetic factors play a big role in obesity, blogs Tom Clarke. The fact we're fatter now than we ever have been before - see our report on the growing size of school uniforms in the last few decades.
Our genes haven't changed much in the last few millions of years, but our lifestyles certainly have. But the biggest reason has to be that this gene is common - two thirds of us have one or two copies of the gene. That means the gene is almost certainly doing something useful (other than just making us fat). If it wasn't you might expect it to have disappeared long ago.
- You're the one for me fatty
Researchers have found genes associated with obesity before -- but they've been very rare, found in people dangerously overweight. What makes the discovery of this new gene, important is that it's common, and strongly linked to body fat.
Over 30,000 people were included in the study and only a third lacked the gene. Around half of them had one copy and on average, those people have 1.2kg more body fat than those without the gene.
One in six people had both copies of the gene- one from mum and and one from dad. Then the effects are, well, large. Those with two copies have, on average, 3kg more fat than those who lack the gene.
It's the strongest link yet to a risk for obesity. So if being overweight has as much to do with genes as lifestyle, is this the end of dieting, and feeling guilty about your weight?
Lola Konstantoplus suffers from type-2 diabetes, one of several serious diseases associated with obesity.
A participant in the study she has now knows she has both copies of the newly discovered gene even though it won't change her life it means a lot to her.
