Plasma levels of adiponectin are paradoxically reduced in obesity, the metabolic syndrome, T2DM and in the presence of CVD [49,50] and increased in response to weight loss and thiazolidinedione (TZD)-induced peroxisome proliferator-activated receptor-gamma (PPAR-γ) activation [51,52]. The gene discussed is ADIPOQ; the disease is obesity due to melanocortin 4 receptor deficiency.