The examination of various inheritance models for TLR9 (T1237C) rs5743836 showed that the dominant one with patients having a mutant TLR9 (T/C) genotype was related to a significantly higher COPD risk development and was the best inheritance model (OR 4.19, 95% CI 2.01 to 8.76, p = 0.001). This evidence concerns the gene TLR9 and chronic obstructive pulmonary disease.