Genetic factors associated with susceptibility to obesity

This review discusses the various genetic factors and gene products (proteins) related to obesity. The three fundamental mechanisms underlying obesity are: relative increase in energy intake; relative decrease in energy expenditure; and preferential partitioning of ingested calories to fat storage. Gene defects can be related to any one of these mechanisms, either alone or together. Many genetic factors are associated with susceptibility to obesity, i.e. over expression in agouti signaling protein or agouti related proteins; leptin deficiency, leptin receptor mutation or deficiency, abnormality in carboxypeptidase pathway, tubby mutation, over-expression ofGLUT4 glucose transporter, serotonin 5-HT2C receptor mutation, and defect in CCK or CCK-A receptor.