Interleukin-18 gene 105A/C genetic polymorphism is associated with the susceptibility of Kawasaki disease

Interleukin-18 (IL-18)-656T/G, -607A/C, and -137C/G promoter polymorphisms had been reported associated with Kawasaki disease (KD). An IL-18 genetic A/C polymorphism at coding position 105 (rs549908) has been linked with asthma, rheumatoid, and systemic lupus erythematosus. We tested a hypothesis that the IL-18 105A/C genetic polymorphism confers KD susceptibility. Study participants were Taiwanese KD patients and a healthy control group. Our data indicated that the frequency of C allele was significantly higher in the patient group (13.9%) than in the control group (2.7%; P<0.0001, odds ratio [OR] = 5.93; 95% confidence interval [CI] = 2.57-13.73). Therefore, persons with the C allele may have higher risk of deve loping KD. In addition, compared with the haplotype frequencies between case and control groups, the KD patients with TACC haplotype appeared to be a significant "at-risk" haplotype compared with other haplotypes (OR: 4.62, 95% CI: 1.71-12.43; P = 0.001). KD patient with the TAGA haplotype appeared to be a significant "protective" haplotype compared with other haplotypes (OR: 0.51, 95% CI:0.29-0.89; P = 0.017). Our results suggest that 105A/C polymorphism and the haplotypes in IL-18 gene are associated with the risk of KD in Taiwanese population.