Investigation of interleukin-23 receptor gene polymorphism in patients with ankylosing spondylitis

Ankylosing spondilit (AS) [MIM 106300], is a chronic progressive inflammatory disease characterized by inflammation of sarcoiliac and spine joint. Although the exact pathogenesis and etiology of AS remains unknown, there are significant outcomes suggesting that genetic factors and certain environmental factors are involved in its development. HLA-B27 positive individuals constitute %90 of AS's while HLA-B27 only partly accounts for the genetic predisposition to this disease. It is also suggested that non-HLA genes may be involved in the development of AS. In this study, distribution of HLA-B27 alleles (+/-) and IL-23R gene rs11209032 polymorphism were investigated among patients who applied to Afyon Kocatepe University, Faculty of Medicine, Department of Physical Therapy and Rehabilitation. The study sample comprised 106 (18 women, 89 men) AS patients who diagnosed 2002 New York criteria's and 82 healthy controls (12 women, 70 men) admitted to Afyon Kocatepe University, Faculty of Medicine, Department of Physical Medicine and Rehabilitation. Distribution of HLAB27 alleles (+)/(-) in AS patients were observed by reverse hybridization technique and genotyping of IL23R rs11209032 polymorphism of AS patients and healty controls was performed by real time PCR. According to obtained results, there were 69 AS patients with HLA-B27 positive (%65.1) and 37 patients with HLA-B27 negative (%34.9). Distribution of rs11209032 genotype frequencies in control group were 34,1% for GG, 53,7% for GA and 12,2% for AA and distribution of rs11209032 genotype frequencies in the AS group were 31,1% for GG, 50,9% for GA and 17,9 for AA. G and A allele frequencies in AS patients were 56,6% and 43,4% respectively, and G and A allele frequencies in controls 60,98% and 39,02% respectively. There were no significant differences between AS patients and controls in terms of genotype frequencies of IL23R gene rs11209032 polymorphism. Consequently, there is no association between AS and IL23R rs11209032 polymorphism for this study group. Key words: Ankylosing spondilit (AS), HLA-B27, IL23R gene, polymorphism