The link between psoriasis and diabetes could, in part, be explained by the rise in obesity and unhealthy lifestyles, the insulin resistance associated with inflammation, and the presence of various genes (CDKAL1, PTPN22, ST6GAL1, JAZF1) linked to both conditions [59,60]. The gene discussed is CDKAL1; the disease is obesity due to melanocortin 4 receptor deficiency.