To delve deep into the link and understand it better, the researchers targeted the Body Mass Index (BMI) and genetics, on five groups of people. The initial study focused on analyzing the DNA and BMI of 700 people, and the team discovered that the presence of two copies of a certain gene variant increased the chances of that person being obese, as the BMI was higher than normal. As is the norm, a BMI of 30 or more is considered obese and a BMI of 25 or more is considered overweight.
Not satisfied with these results and to check out its consistency with other studies on obesity, the researchers sought to probe further. While repeating the same tests on four other groups, that studied almost 4000 people, from different parts of Western Europe, the same results similar to the previous study were shown. The researchers were thus able to see a consistent link between gene variant and obesity.
The researchers also said that nearly ten percent of people have this particular gene variant pattern, and therefore cannot be responsible for all prevailing obesity. The gene variant, called the INSIG2 gene, is concerned with the metabolism of fat and linked to obesity in humans. The aspects of diet and exercise and its influence on obesity, have not been under the purview of study.
The study, published in Science, comes from researchers, led by Alan Herbert, M.BChB., Ph.D., of the genetics and genomics department at Boston University's medical school.