CYP2A6 and chronic obstructive pulmonary disease: These included several important variants or genes associated with COPD or lung function, such as rs2273500 in CHRNA4, rs4488938/rs9654093 in AFAP1, rs72731149 in DTWD1, rs8070954 in SMG6, rs11049488 in CCDC91, rs12894780/rs35584079/rs2180369 in ITPK1, rs503464 in CHRNA5, rs7170068 in CHRNA3, rs116921376 in CYP2F2P/CYP2A6, and rs72927213 in TUT1. The findings of other replication analyses with P-values larger than 0.005 in our population are presented in Supplementary Table S5.