The result showed that higher expression levels of CXCL1 (aOR = 2.19, P = 0.047) and CXCL8 (aOR = 2.36, P = 0.041) were independently associated with significant weight gain, and higher expression levels of CXCL1 (aOR = 3.72, P = 0.037) and TNF (aOR = 2.95, P = 0.033) were independently associated with new-onset obesity postoperatively. The gene discussed is CXCL8; the disease is obesity due to melanocortin 4 receptor deficiency.