200,000 Britons might have appetite gene mutation linked to obesity, according to new study

Scientists find gene mutation could affect weight from early childhood

A study has found that around 200,000 Britons may have a gene mutation that causes them to be heavier from early childhood (Getty Images/iStockphoto)

Scientists have identified a gene mutation that causes some people to have larger appetites and could lead them to weigh, on average, an additional 2.5 stone (17kg) each by the age of 18.

The gene, called MC4R, is responsible for sending signals to the body’s “appetite centres” to tell them how much fat is stored in the body and if we need to eat to store more.

But when the gene is faulty, the brain thinks the body has lower fat stores than it actually does, signalling that it is starving and needs to eat.

The study suggests that around 200,000 people in the UK could carry a “substantial amount of additional fat” because of this mutation.

Researchers from the University of Cambridge and the University of Bristol found that one in every 340 people may carry a mutation of the MC4R gene that causes it to be faulty.

The authors examined the MC4R gene in 6,000 people born in Bristol between 1990 to 1991, who were recruited to long-running health study called Children of the 90s.

Scientists were then able to provide best estimates of the frequency and impact of MC43 mutations on people’s weight and body fat. It was found that people who carry the mutated gene were more likely to have been heavier since early childhood.

By the time they reached the age of 18, they were on average 2.5 stone heavier and majority of the excess weight was likely to be fat.

Professor Sir Stephen O’Rahilly, from the University of Cambridge, said the findings show that weight gain during childhood due to the gene disorder “is not uncommon”.

“Parents of obese children are often blamed for poor parenting and not all children obtain appropriate professional help,” he said.

“This should encourage a more compassionate and rational approach to overweight children and their families - including genetic analysis in all seriously obese children.”

It comes as hospital admissions linked to obesity in England rose above one million for the first time last year.

According to figures from the NHS, there were 1.02 million admissions between 2019 and 2020 for which obesity was either the primary or secondary cause, a 17 per cent uptick from the year before.