Polymorphisms at multiple susceptibility loci in IBD that previously were considered to impact adaptive immunity, similarly could impact ILC phenotype, including RORC, IL23R, IL12RB2, IL12B, IL22, IFNG, STAT1, STAT3, STAT4, CCR6, IL1R1, IL15RA, and IL6ST. 3Accordingly, it is possible that genetic variation at these loci in IBD could impact disease susceptibility by altering the activation and effector function of mucosal ILCs. Here, IL1R1 is linked to inflammatory bowel disease.