Biological influences on obesity.

Severely obese children are even more likely to have mutations in obesity genes than are severely obese adults. Thus, investigators searching for obesity genes commonly focus on children, with the result that many human obesity genes were first identified in studies of children. Although the development of obesity depends on living in an obesity-promoting environment, it also is influenced strongly by individual genetic composition. Thus, the discovery of new obesity genes provides new opportunities to identify causes of severe obesity. Finally, identification of individual causes of obesity may, in the future, provide for a safe, effective, and individualized treatment recommendation for each obese person.