SIRT1 has important functions in glucose and fat metabolism in several tissues, including the adipose tissue, liver, and pancreas [7,8,9,10,11,12], and it has been reported that pharmacological activation of SIRT1 may attenuate metabolic dysfunction linked with obesity and other metabolic dysfunctions [6]. The gene discussed is SIRT1; the disease is obesity due to melanocortin 4 receptor deficiency.