To construct the PPI network, we selected 10 central genes (MMP9, CXCL8, SPP1, CHI3L1, CHIT1, COMP, COL11A1, TNC, MNDA, DCSTAMP) that have a close relationship to both obesity and PTC. The gene discussed is CXCL8; the disease is obesity due to melanocortin 4 receptor deficiency.