Especially the identification of the strong association of a series of single nucleotide polymorphisms including interleukin (IL)-23R, CCR6, signal transducer and activator of transcription 3 (Stat3) and Stat4 with IBD susceptibility point at a critical involvement of T cells and especially of IL-17a-producing Th17 cells in the immune pathogenesis of IBD.
These results suggest that common variants of the CREM gene are involved in the genetic component conferring general susceptibility to IBD, whereas STAT4 appears to be more specifically associated with UC.
We therefore investigated the influence of STAT4 variants on the susceptibility and phenotype of inflammatory bowel diseases (IBD) in a large patient and control cohort.
The association of STAT4 polymorphism rs7574865 with RA was validated in patients of Spanish origin (for T versus G, P = 1.2 x 10(-6), odds ratio [OR] 1.59, 95% confidence interval [95% CI] 1.31-1.92), and the association was described for the first time in both clinical forms of inflammatory bowel disease, Crohn's disease and ulcerative colitis (for T versus G, P = 0.006, OR 1.29, 95% CI 1.07-1.55), and in type 1 diabetes mellitus (for T versus G, P = 0.008, OR 1.36, 95% CI 1.07-1.71).