TYK2 and inflammatory bowel disease: We next interrogated the stability of all CpG loci associated with several well-known GWAS-identified IBD risk genes involved in IBD pathogenesis, namely ATG16L1, NOD2, IL23R, CARD9, FUT2, TYK2, and TNFSF15,49,50 as well as specific IBD-associated major histocompatibility complex encoding HLA genes previously reported on in GWAS studies, namely HLA-DRB1, HLA-DQB1, HLA-DQA1, HLA-DPA1, HLA-DPB1, HLA-A, HLA-B, and HLA-C.49