Relationship between IL-17A gene polymorphism and susceptibility to Kawasaki disease.

Objectives: Kawasaki disease (KD) is the most common autoimmune vasculitis syndrome in children, which supposed be a complex polygenic disorder. Interleukin-17 (IL-17) is a member of the pro-inflammatory cytokine family, which has a strong pro-inflammatory effect and can participate in various acute and chronic inflammatory responses. This study aims to investigate the relationship between the single-nucleotide polymorphism (SNP) locus rs3819025 in the IL-17A gene and the susceptibility to KD.
Methods: A total of 120 patients with KD who met the diagnostic criteria (the KD group) and 120 healthy children (the control group) were enrolled retrospectively in this study. Polymerase chain reaction (PCR) and DNA direct sequencing were used to detect the SNPs of children in the 2 groups.
Results: The frequencies of GG, GA, and AA genotypes of rs3819025 locus in the IL-17A gene in the KD group were 82.5%, 17.5%, and 0, respectively, and the frequencies of GG, GA, and AA genotypes in the control group were 72.5%, 22.5%, and 5.0%, respectively. There were significant differences in both genotype ( χ ² =7.524, P =0.023). The allele frequencies G and A of rs3819025 locus in the KD group were 91.25% and 8.75%, respectively, while those in the control group were 83.75% and 16.25%, respectively. There was significant difference between the 2 groups ( χ ² =6.171, P =0.013). The distribution frequencies of GG or GA genotype and G or A allele were 88.46% or 11.54% and 94.23% or 5.77% in the KD group with coronary artery lesion, respectively. The distribution frequencies of GG or GA genotype and G or A allele were 78.72% or 21.28% and 89 . 36% or 10.64% in the KD group without coronary artery lesion, respectively. There were no significant differences in genotype and allele frequencies of rs3819025 between the KD with coronary artery lesion group and the KD group without coronary artery lesion (both P >0.05). Besides, children with the allele A had a 2.023 times higher risk of KD than those without the allele A ( χ ² =6.171, P =0.013; OR =2.023, 95% CI 1.151 to 3.557).
Conclusions: The locus rs3819025 in the IL-17A gene is associated with the pathogenesis of KD. The allele A of the locus rs3819025 in the IL-17A gene may be a risk factor for KD.