For the homozygote model (OR = 1.460, PZ = 0.001), heterozygote model (OR = 1.275, PZ = 0.007), dominant model (OR = 1.340, PZ = 0.000), recessive model (OR = 1.296, PZ = 0.011) and allele model (OR = 1.254, PZ = 0.000), EPHX1 rs1051740 was significantly associated with COPD risk, indicating that the C allele is a risk factor for COPD. Here, EPHX1 is linked to chronic obstructive pulmonary disease.