Association of interleukin-23 receptor gene polymorphism with Behcet disease.

BACKGROUND: Behcet disease (BD) is a chronic, multisystemic disease characterized by relapsing episodes of a wide spectrum of clinical symptoms. Several genetic and immunological factors have been suggested to be involved in the aetiopathogenesis of BD. AIM: To investigate the association between BD and five single nucleotide polymorphisms (SNP) in the gene for interleukin (IL)-23 receptor (IL-23R). METHODS: We recruited 123 patients with BD and 168 controls. A detailed phenotypic investigation of BD was made for each patient. Five SNPs in the IL-23R gene (rs11209026, rs7517847, rs11805303, rs1004819, rs17375018) were investigated. RESULTS: We found that patients with BD had a lower frequency of the rs17375018 GA and AA genotypes, and a higher frequency of the rs17375018 G allele, and these were statistically significant. The rs11209026 G allele frequency was higher in male patients with BD than in male controls, and the rs7517847 G allele was higher in patients with genital ulcers. The rs11805303 G and rs1004819 G alleles were more frequent in patients with papulopustular lesions. CONCLUSIONS: The rs17375018 variant in the IL-23R gene seems likely to be a strong susceptibility factor for BD in the Turkish population. As this variant was also shown to have a higher frequency in BD patients from different ethnic backgrounds in two previous studies, it may be specific for BD.