Mitogen-activated protein kinases (MAPKs) are vital mediators of cellular signaling associated with the pathogenesis of obesity induced-insulin resistance and T2DM [16], with c-Jun amino-terminal kinase (JNK), P38 protein kinase, and extracellular-regulated kinase (ERK) being the principle relevant MAPKs [17]. The gene discussed is MAPK8; the disease is obesity due to melanocortin 4 receptor deficiency.