Associations Between Polymorphisms of IL-17F and IL-17A Genes with Disease Activity and Clinical Outcome of Ankylosing Spondylitis

Methods: The study included 101 AS patients and 106 healthy controls. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels, in addition to scores of the Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Metrology Index and Bath Ankylosing Spondylitis Functional Index (BASFI) of the patients, were recorded. The frequencies of genotypes 7383A/G and 7488A/G of the IL-17F and G197A of IL-17A genes and alleles were compared between the patients and healthy controls.

Major Results: There were significant differences in the allele frequencies and genotype distribution of IL-17F 7488A/G. There were also significant differences in the CRP levels and BASFI scores of patients due to the genotype distribution of the IL-17F 7488A/G polymorphism (p= 0.029, 0.045, respectively).

Conclusions: This study suggests that the IL-17F 7488A/G polymorphism may be associated with susceptibility to AS, disease activity and functional status in Turkish patients. Further studies with larger numbers of AS patients, with a long-term follow-up, are needed to elucidate the observed relations.