Obesity, defined as an excessive body fat accumulation, is caused by a chronic imbalance between energy intake and energy expenditure. Several factors have been associated with this energy imbalance, such as life style (diet and physical activity), neuroendocrine disorders, together with the genetic background. The genetic background is a major determinant factor of some congenital diseases and a risk factor for some chronic disorders, such as diabetes, osteoporosis, hypertension, cancer, obesity, and others. The increased prevalence of obesity in most countries during the last years, seems to indicate that there is a genetic predisposition or susceptibility to be obese which is increased by environmental and life style factors, mainly by food habits and physical in activity. The use of obesity animal models, genetic transfer and the association and linkage studies leaded to the identification of many genes associated with obesity.
obesity; genes; mutation; polymorphism; obesity genetic models; association and linkage studies
