Identification of genetic variants of the <i>IL18R1</i> gene in association with COPD susceptibility

Although existing studies have identified some genetic loci associated with chronic obstructive pulmonary disease (COPD) susceptibility, many variants remain to be discovered. The aim of this study was to further explore the potential relationship between IL18R1 single nucleotide polymorphisms (SNPs) and COPD risk. Nine hundred and ninety-six subjects were recruited (498 COPD cases and 498 healthy controls). Five candidate SNPs of IL18R1 were selected and genotyped using MassARRAY iPLEX platform. Logistic regression analysis was performed to assess the association of these SNPs with COPD risk. Multifactor dimensionality reduction (MDR) software was applied to calculate the interaction of SNP-SNP on COPD risk. IL18R1 rs9807989 (OR = 0.42, p < .001), rs3771166 (OR = 0.40, p < .001) and rs6543124 (OR = 0.44, p < .001) were associated with the reduced COPD risk, while rs2287037 (OR = 2.71, p < .001) and rs2058622 (OR = 2.06, p < .001) might be the risk-increasing factor for COPD occurrence in both the overall analysis and subgroup analysis (age, gender, drinking, and smoking). The best multi-locus model was the combination of rs2058622 and rs3771166. Our study provided a reference and basis for investigating the association of IL18R1 polymorphisms with COPD risk.