In fact, the deregulation of the SIRT1-mediated pathway is closely associated with a range of metabolic alterations, as observed in a SIRT1 adipose-specific knockdown mouse model which resulted in fat accumulation, alterations in glucose and lipid metabolism, as well as impaired insulin sensitivity, and the development of obesity [12]. The gene discussed is SIRT1; the disease is obesity due to melanocortin 4 receptor deficiency.