Obesity contributes to a pro-inflammatory state that exacerbates psoriasis by secreting adipokines, such as leptin and resistin, which stimulate Th17 and Th1 cells, thereby increasing Il-17 and TNF-a cytokines, key factors involved in the pathogenesis of psoriasis [72,73]. The gene discussed is RETN; the disease is obesity due to melanocortin 4 receptor deficiency.