Association of IL-17A and IL-10 Polymorphisms with Juvenile Idiopathic Arthritis in Finnish Children

Abstract

To analyze the role of interleukin <i>IL-17A</i> and <i>IL-10</i> polymorphisms in susceptibility to juvenile idiopathic arthritis (JIA), 98 Finnish children and adolescents with JIA were studied. Data from the 1000 Genomes Project, consisting of 99 healthy Finns, served as the controls. The patients were analyzed for four <i>IL-17A</i> and three <i>IL-10</i> gene-promoter polymorphisms, and the serum IL-17A, IL-17F, IL-10, and IL-6 levels were determined. The <i>IL-17A</i> rs8193036 variant genotypes (CT/CC) were more common among the patients than controls, especially in those with polyarthritis (OR 1.93, 95% CI 1.11-3.36; <i>p</i> = 0.020). <i>IL-17A</i> rs2275913 minor allele A was more common in patients (OR 1.45, 95% Cl 1.08-1.94; <i>p</i> = 0.014) and especially among patients with oligoarthritis and polyarthritis than the controls (OR 1.61, 95%CI 1.06-2.43; <i>p</i> = 0.024). Carriers of the <i>IL-17A</i> rs4711998 variant genotype (AG/AA) had higher serum IL-17A levels than those with genotype GG. However, carriers of the variant genotypes of <i>IL-17A</i> rs9395767 and rs4711998 appeared to have higher IL-17F levels than those carrying wildtype. <i>IL-10</i> rs1800896 variant genotypes (TC/CC) were more abundant in patients than in the controls (OR 1.97, 95%CI 1.06-3.70; <i>p</i> = 0.042). Carriers of the <i>IL-10</i> rs1800896 variant genotypes had lower serum levels of IL-17F than those with wildtype. These data provide preliminary evidence of the roles of <i>IL-17</i> and <i>IL-10</i> in the pathogenesis of JIA and its subtypes in the Finnish population. However, the results should be interpreted with caution, as the number of subjects included in this study was limited.