Genetically predicted higher level of HADH (OR = 0.42, 95%CI: 0.27–0.63, PPH4 = 0.98) was associated with a decreased risk of IBD, while higher levels of CXCL9 (OR = 2.12, 95%CI: 1.39–3.25, PPH4 = 0.99) and HP (OR = 1.09, 95%CI: 1.04–1.14, PPH4 = 0.79) were associated with an increased risk of IBD. The gene discussed is CXCL9; the disease is inflammatory bowel disease.