Science: Researchers Discover Gene Variant Linked to Obesity, Type 2 Diabetes

A particular gene variant appears to make some individuals more vulnerable to obesity, a risk factor for Type 2 diabetes, according to new research published online 12 April by Science, at the Science Express website.

Analyzing 13 studies with approximately 38,500 participants of all ages, Andrew Hattersley, professor of molecular medicine at Peninsula Medical School at the University of Exeter, and colleagues found that participants with a specific copy of the FTO gene tended to have an elevated Body Mass Index (BMI), a general measure of health calculated by comparing height and weight.

The researchers found that the common gene variant, found in perhaps two-thirds of white Europeans, increased an individual's risk of obesity by up to 67 percent.

The author's point out that while the FTO gene variant was associated with only a modest increase in weight, it can lead to obesity and Type 2 diabetes in a populations like the U.S. where 66 percent of people are overweight and one-third are obese.

"The gene variant appears to influence how much fat people have, perhaps predisposing people to obesity and therefore Type 2 diabetes," Hattersley said in a teleconference for reporters.

While the article does suggest at least a partial genetic basis for obesity, the researchers emphasized that diet and exercise are extremely important for staying healthy.

"Obesity is a major cause of morbidity and mortality, associated with an increased risk of type 2 diabetes mellitus, heart disease, metabolic syndrome, hypertension, stroke, and certain forms of cancer," the authors wrote.

One of the studies in the article examined approximately 2,000 participants with Type 2 diabetes and approximately 3,000 people without the disease, documenting a strong association between the gene copy and Type 2 diabetes.

Additionally, by studying two large groups of children from birth to age 14, the scientists determined that the gene copy begins to affect BMI around age 7.

Although the authors don't yet know the overall role the FTO gene plays in the body, nor how the FTO gene affects BMI, they believe further studies "may provide insights into novel pathways involved in the control of adiposity (fat storage)."

Kathy Wren and Benjamin Somers

12 April 2007