Ruhr-Universitat Bochum in Germany also collaborated on the study, and provided the patient population which was studied. There is increasing evidence that genetic factors lead to obesity, but the exact genes involved have not been defined. Previously, researchers had pinpointed a mutation in the coding sequence of the leptin gene and the leptin-receptor gene as being linked to obesity, but screening of thousands of obese subjects have identified this defect in only a very few obese individuals. In this study, the researchers investigated 358 unrelated German people, including 121 whom were deemed obese, with a body-mass index greater than 29. All of the subjects with the mutant gene were markedly obese, with body mass indexes ranging from 37.9 to 47.3, compared with an average of 33.6 in the other obese subjects.
Obesity is the most common health problem in developed countries.
It is the second most common cause of preventable death in the United States. Obesity in humans is believed to result from a combination of environmental influences and genetic factors that affect energy storage and caloric intake. More simply put, it results from an imbalance between chronic energy intake and energy expenditure. Previous studies in twins suggestion that up to 80 percent of obesity is attributable to genetic factors. People who are obese are at a markedly increased risk of developing type 2 diabetes, which affects an estimated 16 million Americans and is a leading cause of heart disease, strokes, kidney disease and premature death.