While dipeptidyl peptidase IV (DPP-IV) is a surface antigen protein involved in the cleavage of the glucagon peptide-like 1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) involved in the potentiation of pancreatic cells to secrete insulin [10, 11], PTP-1B catalyzes the dephosphorylation of insulin receptors (IR) and insulin receptor substrates (IRS) concerned with type-2 diabetes mellitus (T2DM) pathogenesis and obesity inducing insulin and leptin resistance, respectively [12]. The gene discussed is GCG; the disease is obesity due to melanocortin 4 receptor deficiency.