Relationships of interleukin-17 polymorphisms with recurrent aphthous ulcer risk in a Han Chinese population

OBJECTIVE: Interleukin (IL)-17 is a multifunctional cytokine with important roles in inflammatory and autoimmune diseases. This case–control study explored the relationships of IL-17A rs2275913 and IL-17F rs763780 single-nucleotide polymorphisms (SNPs) with recurrent aphthous ulcer (RAU) morbidity and severity. METHODS: IL-17A rs2275913 and IL-17F rs763780 SNPs were measured in 125 patients with RAU and 116 healthy control participants. The genotype distributions, disease risks, and relationships with RAU severity were analyzed. RESULTS: RAU risk was associated with rs2275913 after adjustment for age, body mass index, sex, smoking status, and drinking status (AA vs. GG: odds ratio [OR], 2.759; 95% confidence interval [CI], 1.381–5.512; A allele vs. G allele: OR, 1.783; 95% CI, 1.242–2.560). TC and CC genotypes in rs763780, and the corresponding C allele, demonstrated greater prevalence among patients with RAU, compared with the TT genotype (TC vs. TT, OR: 1.895; 95% CI: 1.088–3.301; CC vs. TT, OR: 4.080, 95% CI: 1.079–15.425; C allele vs. T allele, OR: 1.969, 95% CI: 1.257–3.083). Serum IL-17 concentrations were also higher in patients with RAU than in control participants. These concentrations were associated with IL-17 polymorphisms. CONCLUSIONS: IL-17 polymorphisms might be associated with greater risk of RAU pathogenesis.