IL-6 and TNF variants as potential determinants of perianal disease in Crohn's patients: a pilot study

Perianal Crohn's disease (pCD) is a debilitating complication of Crohn's disease (CD), affecting approximately 20 % of patients. Genetic polymorphisms in cytokine-related and intracellular signaling pathway genes may influence pCD development, yet data on their role remain limited. To evaluate the association between specific single nucleotide polymorphisms (SNPs) in cytokine (TNF, IL-6, IL-10, TGF-β) and MAPK pathway-related genes (RAS, RAF-1, ERK) and the pCD development. This retrospective study included 204 CD patients from a single center, of whom 34 had documented pCD. Clinical, phenotypic, and treatment data were collected. Genotyping was performed by real-time PCR and ARMS-PCR. IL-6 -597 GG genotype was significantly associated with a reduced risk of pCD (p = 0.049). TNF rs1800629–308 GA genotype showed a trend toward protection (p = 0.07). IL-10 -1082 AA genotype showed a non-significant trend toward increased risk (p = 0.07). No significant associations were found for TGF-β or MAPK-related polymorphisms. Our findings suggest that polymorphisms in cytokine genes, particularly IL-6 and TNF, may influence the risk of developing perianal complications in CD. These preliminary results warrant validation in larger cohorts to assess their potential as predictive biomarkers for personalized management of pCD.