Exploring the Contribution of Interleukin-17 Genetic Polymorphisms to Pterygium Risk

Pterygium is a chronic, fibrovascular ocular surface disorder with tumor-like biological behavior. Although inflammatory mediators such as interleukin-17 (IL17) are increasingly implicated in its pathogenesis, the genetic contribution of IL17 remain unclear. To our knowledge, this study is the first to investigate whether IL17A rs2275913 and IL17F rs763780 polymorphisms influence pterygium susceptibility in a Taiwanese population.

This case-control study evaluated the association between promoter IL17A rs2275913 and exonic IL17F rs763780 polymorphisms with pterygium susceptibility in 160 patients and 320 age- and sex-matched controls by polymerase chain reaction-restriction fragment length polymorphism methods. The potential interactions between IL17A genotype and age or sex were tested by stratified analysis.

IL17A rs2275913 genotype distribution showed borderline overall significance (p for trend=0.0522). Compared with GG carriers, individuals with AG and AA genotypes exhibited odds ratios (ORs) 1.39 [95% confidence interval (CI)=0.91-2.13, p=0.1546] and 1.92 (95%CI=1.11-3.30, p=0.0263), respectively. Under the dominant model (AG+AA vs. GG), risk of pterygium was increased significantly (OR=1.53, 95% CI=1.03-2.27, p=0.0449). The A allele conferred elevated susceptibility (OR=1.42, 95% CI=1.08-1.87, p=0.0136). No significant associations were observed for IL17F rs763780 (all p>0.05). Stratified analyses indicated significant increased effects of IL17A rs2275913 genotype by older age (≥60 years), and female sex.

Our findings demonstrate, for the first time, that IL17A rs2275913, particularly the A allele and AA genotype, is associated with increased pterygium risk among Taiwanese individuals, with stronger effects among older adults and females. These results suggest a potential genetic basis for IL17-mediated inflammation in pterygium and highlight IL17A rs2275913 as a promising biomarker for pterygium susceptibility.