200,000 Britons have appetite gene that adds two stone

Many more people have a defective version of the gene than thought, the University of Cambridge study suggests
Many more people have a defective version of the gene than thought, the University of Cambridge study suggests
TERO VESALAINEN/GETTY IMAGES

Scientists have made a breakthrough in unravelling the genetics of obesity by identifying a single gene that is likely to cause 200,000 people in the UK to weigh, on average, an extra two and a half stone each.

The gene, MC4R, has an influence on appetite that begins in childhood. When a person has a faulty variant of the gene their brain is told, in effect, that their body is starving, compelling them to eat.

By 18 they are, on average, about two-and-a-half-stone heavier than peers who do not have the defective variant of the gene, with the excess weight likely to be mostly fat, a study suggests.

MC4R had been linked to weight but research published today in Nature Medicine indicates that the effects