Association of Familial Mediterranean Fever-Related MEFV Variations With Ankylosing Spondylitis

Objective. The pathogenesis of ankylosing spondylitis (AS) has a strong genetic contribution. Familial Mediterranean fever (FMF) is an autosomal recessively inherited autoinflammatory disorder caused by MEFV gene missense variations, and a clinical association between FMF and AS has been reported previously. The aim of this study was to analyze the association of common MEFV variations (M694V, M680I, V726A, and E148Q) with AS in a group of Turkish patients. Methods. The study group comprised 193 patients with AS and 103 matched healthy control subjects. All individuals were genotyped for 4 MEFV variations and HLA-B27 using genomic DNA, and association of the variations with the clinical and laboratory features of the patients was analyzed. Results. The MEFV missense variations were significantly more frequent in patients with AS (22.3%) compared with healthy control subjects (9.7%; odds ratio [OR] 2.67, 95% confidence interval [95% CI] 1.28-5.56). This difference was more prominent for exon 10 variations (M694V, V726A, M680I) (OR 3.75, 95% CI 1.41-9.97), especially for the most-penetrant variation M694V (OR 4.73, 95% CI 1.39-16.12). MEFV variations were more frequent in HLA-B27-negative patients with AS, and the difference was statistically significant in patients carrying exon 10 variants. Conclusion. FMF-related MEFV variations are associated with AS, and these variations may contribute to the pathogenesis of AS, especially in populations in which the prevalence of FMF is high.