MAPK3 and obesity due to melanocortin 4 receptor deficiency: Functional enrichment analysis showed that MAPK3 was involved in natural killer cell-mediated cytotoxicity[45–47], proteoglycans in cancer, the Rap1 signaling pathway[48] and the Ras signaling pathway[49, 50] and 124 GO biological process terms, which showed the important role of MAPK3 in obesity[44–50].