IBD & Mucosal Immunity

Intronic IL-23 receptor variant that increases susceptibility to ankylosing spondylitis and inflammatory bowel disease by enhancing IL-23/Th17 inflammatory signaling

Rare NOD2 missense variant (Ser431Leu) that reduces NF-κB activation in response to bacterial muramyl dipeptide, independently associated with Crohn's disease risk; often co-inherited on a haplotype with the V793M variant

Rare NOD2 missense variant (Val793Met) identified in IBD deep-resequencing; contributes to Crohn's disease risk primarily in compound heterozygous state with other NOD2 variants

Intronic IL23R variant in LD block 2 where the T allele is associated with increased susceptibility to Crohn's disease and ankylosing spondylitis while the C allele is protective — a signal distinct from the rs1004819/rs7517847 haplotype block

Intergenic variant near JAK2 that increases JAK2 expression and JAK-STAT signaling, disrupting intestinal barrier function and increasing IBD susceptibility

3' UTR and intronic IL23R variant disrupting Let-7e/Let-7f miRNA binding — the A allele elevates IL-23 receptor expression and is associated with ankylosing spondylitis, inflammatory bowel disease, and rheumatoid arthritis susceptibility; the C allele was independently associated with Graves' ophthalmopathy in a Caucasian cohort

Strongly protective variant against inflammatory bowel disease and other autoimmune conditions through impaired IL-23 signaling

5' UTR variant in the beta-defensin 1 gene that reduces antimicrobial peptide expression in gut and mucosal epithelium, increasing susceptibility to colonic Crohn's disease and dental caries

Intronic IL23R variant in strong linkage disequilibrium with the functional R381Q variant (rs11209026); the minor G allele tags the protective haplotype that dampens IL-23 receptor signalling, reducing risk for ankylosing spondylitis, Crohn's disease, ulcerative colitis, and psoriasis

Regulatory variant upstream of the IL-23 receptor gene more strongly associated with psoriatic arthritis than cutaneous psoriasis alone, implicating distinct Th17 signaling at the joint versus skin interface

Zinc and manganese transporter variant that reduces metal ion absorption, affecting gut barrier function and microbiome composition

Autophagy regulator affecting bacterial clearance in the gut and Crohn's disease susceptibility

Intronic IL23R variant whose minor A allele tags the protective haplotype for ankylosing spondylitis and Crohn's disease while representing an independent susceptibility signal for rheumatoid arthritis

Intergenic variant between IL23R and IL12RB2 on chromosome 1p31.3 associated with increased risk of ankylosing spondylitis, Behçet's disease, and Crohn's disease through IL-23 pathway dysregulation

Missense variant in the NOD2 gene that increases Crohn's disease risk, particularly ileal disease, by impairing bacterial peptidoglycan recognition

MTX1 intronic variant at 1q22 tagging a gastric cancer susceptibility locus that regulates mucosal integrity via the MUC1/UBAP2L axis

Autophagy gene variant affecting bacterial clearance in gut epithelial cells, strongly associated with Crohn's disease risk

Regulatory variant in the PSCA 5′ UTR that recruits the repressor YY1 to the promoter, suppressing PSCA expression in gastric epithelium and increasing susceptibility to diffuse-type gastric cancer and gastric mucosal atrophy

Intronic variant in FGFR1OP (CEP43) at the RNASET2-FGFR1OP-CCR6 autoimmune susceptibility locus, with the T allele increasing risk for Crohn's disease

Macrophage-stimulating protein variant affecting innate immune response and IBD susceptibility

Mucin-1 gene variant affecting gastric mucus barrier function and H. pylori colonization resistance

Gain-of-function missense variant in the CARD9 adaptor protein that enhances antifungal immune signaling, increasing susceptibility to inflammatory bowel disease and allergic bronchopulmonary aspergillosis

Second intronic enhancer variant in SMAD3 that modulates TGF-beta effector signaling in regulatory T cells, influencing susceptibility to autoimmune and inflammatory conditions including IBD

Intronic IRGM variant raising risk for Crohn's disease — particularly ileal disease and fistulizing complications

Intronic IL23R variant where the minor T allele is associated with increased ankylosing spondylitis susceptibility

Promoter variant in the PTGS2/COX-2 gene that reduces baseline COX-2 expression, increasing susceptibility to ulcerative colitis and modifying colorectal cancer and cardiovascular risk

Intronic variant in CDKAL1, a tRNA methylthiotransferase gene; the C allele is associated with increased risk of Crohn's disease and shared pleiotropic risk for psoriasis through immune cell expression of CDKAL1

Intronic ELMO1 variant acting as an eQTL that modulates engulfment and cell motility protein expression in thymic and peripheral immune cells, with GWAS associations with celiac disease, primary biliary cholangitis, and inflammatory bowel disease

Intronic IL23R variant in which the T allele increases susceptibility to Crohn's disease, ulcerative colitis, and ankylosing spondylitis, while the G allele is protective — independent of the rs2201841 risk signal at the same locus

Missense variant in the IL-23 receptor that substitutes leucine for proline at position 310; the rare leucine allele (T) is associated with susceptibility to Graves' disease and rheumatoid arthritis through altered IL-23/Th17 immune signaling