Resistin has been regarded as an important link between obesity and T2DM from our own previous studies, suggesting how central obesity and abdominal adipocytes play a role in promoting resistin and other pro-inflammatory cytokines via the nuclear factor–κB signaling pathway [45,46], which has also been noted in human macrophages and peripheral mononuclear cells [47]. The gene discussed is RETN; the disease is obesity due to melanocortin 4 receptor deficiency.