Study: Obesity Has Genetic Component

Researchers in England believe that they have discovered the “most clear genetic link yet to obesity in the general population.” According to the study, those with two copies of a particular gene variant face a 70 percent higher risk of being obese when compared to individuals with no copies of that variant. The discovery of the so-called “fat gene” has been hailed as a major breakthrough.

The research, which was funded by the Wellcome Trust, the UK’s largest medical research charity, appears in the current issue of the journal Science. Scientists from the Peninsula Medical School in Exeter and the University of Oxford first identified a genetic link to obesity after studying 2,000 people with type-2 diabetes plus 3,000 control subjects. “Through this genome-wide study,” the Wellcome Trust reports, “the researchers identified a strong association between an increase in BMI [body mass index] and a variation, or ‘allele,’ of the gene FTO.”

To follow up this discovery, researchers then sampled 37,000 other patients in the U.K. and Finland in searching for this particular gene. “The study found that people carrying one copy of the FTO allele have a 30 percent increased risk of being obese compared to a person with no copies. However, a person carrying two copies of the allele has a 70 percent increased risk of being obese, being on average 3 kg heavier than a similar person with no copies. Among white Europeans, approximately one in six people carries both copies of the allele.”

One of the researchers, professor Andrew Hattersley of the Peninsula Medical School, said, “Our findings suggest a possible answer to someone who might ask ‘I eat the same and do as much exercise as my friend next door, so why am I fatter?’ There is clearly a component to obesity that is genetic.”

“Even though we have yet to fully understand the role played by the FTO gene in obesity, our findings are a source of great excitement,” added Professor Mark McCarthy from the University of Oxford. “By identifying this genetic link, it should be possible to improve our understanding of why some people are more obese, with all the associated implications such as increased risk of diabetes and heart disease. New scientific insights will hopefully pave the way for us to explore novel ways of treating this condition.”

The findings have significant implications for the treatment of diabetes and heart disease. Because of the gene’s effect on BMI, researchers extrapolated that having one copy of the FTO variant increases the risk of developing type-2 diabetes by 25 percent, while having two copies of the variant increases the risk by a whopping 50 percent.