Genetic association analysis of and gene single-nucleotide polymorphisms and Crohn's disease.

Background: Crohn's disease (CD) is characterized by a multifactorial etiology and a significant impact of genetic traits. While mutations represent well established risk factors of CD, the role of other genes is incompletely understood.

Aim: To challenge the hypothesis that single nucleotide polymorphisms (SNPs) in the genes and , two members of the C-type lectin domain family of pattern recognition receptors, may be associated with CD.

Methods: SNPs in , and the known CD risk gene were studied using real time PCR-based SNP assays. Therefore, DNA samples from 175 patients and 157 healthy donors were employed. Genotyping data were correlated with clinical characteristics of the patients and the results of gene expression data analyses.

Results: In accordance with previous studies, rs2066844 and rs2066847 in were found to be significantly associated with CD (allelic values = 0.0368 and 0.0474, respectively). Intriguingly, for genotype AA of rs1285933 in , a potential association with CD (recessive = 0.0523; odds ratio = 1.90) was observed. There were no associations between CD and SNPs rs2078178 and rs16910631 in . Variants of rs1285933 had no impact on gene expression. In contrast, genotype-dependent differences of expression in peripheral blood mononuclear cells were observed. There is no statistical interaction between the tested SNPs of and , suggesting of a novel pathway contributing to the disease.

Conclusion: Our data encourage enlarged follow-up studies to further address an association of SNP rs1285933 in with CD. The C-type lectin domain family member also deserves attention regarding a potential role in the pathophysiology of CD.