Synonymous mutations in TLR2 and TLR9 genes decrease COPD susceptibility in the Chinese Han population

Introduction: Previous studies have found associations between polymorphisms in some candidate genes and chronic obstructive pulmonary disease (COPD) risk. However, the association between TLR2 and TLR9 polymorphisms and COPD risk remains uncertain. Methods: Four variants (rs352140, rs3804099, rs3804100, and rs5743705) of the TLR2 and TLR9 genes in 540 COPD patients and 507 healthy controls were genotyped using the Agena MassARRAY system. Odds ratio (OR) and 95% con fidence interval (CI) were calculated to assess the association of TLR2 and TLR9 polymorphisms with COPD risk by logistic regression analysis. Results: TLR9 -rs352140, TLR2 -rs3804100, and TLR2 -rs5743705 were related to a lower risk of COPD among Chinese people and the signi ficance still existed after Bonferroni correction. Additionally, rs3804099, rs3804100, and rs352140 were found to be associated with COPD development in different subgroups (males, age < 68 years, smokers, BMI < 24 kg/m(2), and acute exacerbation). Conclusions: Our findings indicated that TLR9 and TLR2 polymorphisms had protective effects on the development of COPD among Chinese people.