The strongest association with FEV1/FVC ratio among smokers was observed with rs9322335 in 1(ESR1) on chromosome 6. The second strongest association was rs1864271 in with rhomboid domain containing 1 (RHBDD1) on chromosome 2, followed by rs1738567 in (MTHFD1L) on chromosome 6. The region association plots for SERPINA1 and PDE4D among ever-smokers (figure 2) show some supportive evidence for the association of these two loci. The region association plots for the additional loci among ever-smokers reported in table 1 are shown in figure S2 in the online supporting information.
