IRF1 and inflammatory bowel disease: Similarly, the MS-associated variant rs1800693 colocalizes with tumor necrosis factor receptor superfamily member 1A (TNFRSF1A) alternative splicing in monocytes and neutrophils; the rs917997 CEL variant colocalizes with interleukin 18 receptor accessory protein (IL18RAP) alternative splicing in neutrophils, rs35260072 (IBD) colocalizes with interferon regulatory factor 1 (IRF1) splicing in neutrophils; and the rs12936409 IBD/CD variant (Anderson et al., 2011) colocalizes with gasdermin B (GSDMB) splicing in T cells.