The rs2275913 polymorphism of the interleukin-17A gene is associated with the risk of ovarian endometriosis

Abstract

The aim of this study was to explore the relationship between two genetic variants (rs2275913 and rs3748067) of interleukin-17A (IL-17A) and the risk of ovarian endometriosis in northern Chinese women. This study was performed in 316 patients with ovarian endometriosis and 328 female control subjects. The genotypes of the two polymorphisms were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The mRNA expression of IL-17A was detected by quantitative real-time PCR (qRT-PCR). There was a significant difference in the genotype distributions of the rs2275913 polymorphism between the patients and control subjects (p = .006). Compared with the GG genotype of rs2275913, the AA genotype was correlated with a higher susceptibility to the development of ovarian endometriosis (OR = 2.28, 95% confidence interval (CI) = 1.37–3.80). Furthermore, the levels of IL-17A mRNA were higher in the ectopic endometrium from ovarian endometriosis patients carrying the rs2275913 AA genotype than in those carrying the rs2275913 GG genotype (p = .007). This study suggested that the rs2275913 polymorphism at the promoter region of IL-17A may be a functional genetic variant, and the rs2275913 AA genotype is associated with a higher risk of developing ovarian endometriosis in northern Chinese women. IMPACT STATEMENT What is already known on this subject? Interleukin-17A (IL-17A) is a crucial proinflammatory and angiogenic cytokine that has been shown to participate in the pathogenesis of chronic inflammatory and autoimmune diseases. Genetic variants in IL-17A may alter the expression of the IL-17A, and are associated with the susceptibility to a wide range of human diseases. What do the results of this study add? This study suggested that the rs2275913 polymorphism at the promoter region of IL-17A may be a functional genetic variant that affects the expression of IL-17A mRNA in ectopic endometrial tissues. The AA genotype of rs2275913 was associated with a higher risk of developing ovarian endometriosis in northern Chinese women. What are the implications of these findings for clinical practice and/or further research? IL-17A may be a potential biomarker for early diagnosis and gene-targeted therapy of ovarian endometriosis.