The ADRB3 Trp64Arg locus acts as a “thrifty” gene and has already been reported associating with obesity,[36] hypertension,[37] diabetes mellitus,[8] insulin resistance,[38] and glycolipid metabolism.[39] Logically, ADRB3 Trp64Arg locus may play an important role in the pathogenesis of CAD. This evidence concerns the gene ADRB3 and obesity due to melanocortin 4 receptor deficiency.