British Scientists Discover Gene that Contributes to Obesity

By Erin Peterson

British researchers have discovered a gene that can be linked to increased body fat and will help to explain why some people weigh more than others regardless of similar lifestyles.

Scientists classify this particular strand of DNA as the FTO gene. It was found to be a common trait in people with type 2 diabetes, but the gene does not affect insulin production. Rather, the gene is found to be associated with increased body fat.

After making this association, scientists looked into DNA databases to see if other studies revealed that the gene may predispose a person to obesity. The research found that a strain of FTO was closely correlated with obesity in other findings as well.

Scientists concluded that those having one copy of the FTO gene are 30% more likely and those with two copies of the gene are 70% more likely to be obese than those with a different version of the gene.

The study sample included mostly white European adults. More than 38,000 blood samples were viewed and analyzed for common characteristics. One in six of the samples was found to carry two copies of the FTO gene.

While this gene may explain why some people are more predisposed to weight gain than others, it should not take all of the blame. Research findings show that the presence of this gene causes carriers to gain only around seven pounds more than others.

Bad diet and lack of exercise are still the chief cause why about one-third of Americans are obese and twice that many are overweight. Overweight is classified by a body mass index (BMI) of 25 or more and obesity by a BMI of 30 or more. Body mass index is an indicator of body fatness based on a calculation of a person’s weight and height.

In the British study, scientists did not specify the diet and exercise habits of the sample population so researchers were not able to infer any correlation between lifestyle choices and the gene.

"We know very little about how different versions of this gene alter how much fat you have. It could influence your appetite, your tolerance to exercise, or your metabolic rate. The next steps will be to address these questions," notes researcher Timothy Frayling, PhD.

One possible course for future research would be to study how people with different copies of the FTO gene respond to various diet and exercise regimes.

The more that can be learned about the FTO gene, the more information medical researchers will have to design weight loss drugs or programs for obese individuals and diseases such as heart disease and diabetes.

"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," said Oxford University professor Mark McCarthy. "New scientific insights will hopefully pave the way for us to explore novel ways of treating this condition."

So far, researchers have studied only the DNA of white Europeans, but they feel confident that the findings will be similar in other ethnic groups. They hope to repeat their study on African Americans and South Asians next, as both populations have documented problems with obesity and related problems.

Obesity is the leading cause of many long-term health issues like heart disease, cancer, and type 2 diabetes. A recent U.S. government report shows that obesity and its related illnesses are now the top cause of medical spending and concern in the United States – overtaking smoking or alcohol.