By Mark Huffman
ConsumerAffairs.com
April 13, 2007
While poor diet and lack of exercise explain most cases of obesity, researchers say there may be a reason why some people have trouble loosing weight, no matter what they do: it's in the genes.
British scientists say people who inherit a certain gene are up to 70 percent more likely than others to be obese. They say one in six people may have this unusual genetic makeup and have as much as 15 percent more body fat than people without the gene variation.
Researchers at the University of Oxford say their discovery may signal a breakthrough in treating obesity.
Identifying the obesity gene, they say, could lead to development of a drug that would help affected people better control their weight.
How common is the obesity gene? Researchers say they can't yet answer that question. They also stress that the gene itself doesn't make people overweight, it simply increases the risk, by making it harder for them to shed body weight.
Obesity is a main cause of heart disease, cancer and type 2 diabetes. Health officials worldwide have expressed alarm at its growth in recent years, with some saying its now a bigger health issue than smoking and alcohol abuse.
The findings are published in Science, the journal of the American Association for the Advancement of Science.
Gene Found in Diabetics
The scientists discovered the gene, known as FTO, in a study of 2,000 diabetics when they were doing a genome-wide search for susceptibility to type 2 diabetes. They found there was a strong link between the FTO variant and body mass index (BMI).
They conducted another study on 13 cohorts of 38,759 Britons, Finns and Italians aged 7 and above where they found a similar link between the FTO variant and body weight.
The strength of the genetic influence depends on whether an individual has inherited one or two copies of the FTO gene variant, researchers said. A person with two copies of the FTO variant is likely on average to weigh 6.6 pounds more than a person who does not have the FTO variant at all, and if they have only one copy they are likely on average to weigh 2.6 pounds more.
The researchers said their findings reinforce findings from twin studies that suggest obesity is driven partly by genes. However, they added that lifestyle and environment are also strong factors. The genetics has not changed in the last 100 years, but lifestyle and environment has, they said.
