Association Study of Genetic Variants in miRNAs in Patients with Inflammatory Bowel Disease: Preliminary Results

Aberrant expression and structural alteration of miRNAs are considered to participate in inflammation and cancer development. It has been suggested that common single-nucleotide polymorphisms (SNPs) in miRNAs are associated with susceptibility to several human diseases. In the present preliminary study we evaluated the associations of two SNPs (rs2910164 and rs11614913 in miR-146a and miR-196a2, respectively) with the risk of inflammatory bowel disease (IBD) in a Greek population. The rs2910164 and rs11614913 SNPs were genotyped in 242 patients with Crohn's disease (CD), 210 patients with ulcerative colitis (UC) and 300 healthy individuals. No statistically significant differences were found in the genotype or allele distributions of the rs2910164 SNP among UC and control subjects. However, significant differences were found in the genotype or allele distributions of the rs2910164 polymorphism among CD and control subjects (P < 0.0001 and P < 0.0001, respectively). Concerning the rs11614913, no statistically significant differences were found in the genotype or allele distributions among CD and control patients, whereas TT genotype and T allele seem to have a protective role against UC (P = 0.017 and P = 0.007, respectively). The presence of rs2910164 and rs11614913 SNPs did not influence disease phenotype. Our results demonstrate that the rs2910164 polymorphism has a major role in genetic susceptibility to CD but not to UC, since the rs11614913 polymorphism had a protective role against UC, at least in the population studied here. Independent studies are needed to validate our findings in larger series and in patients of different ethnic origins.