IREB2 and chronic obstructive pulmonary disease: There is some evidence that the modifier effects of IREB2 and CHRNA3 may be more prominent in males (rs2568494, rs8034191, and rs1051730 for post-bronchodilator FEV1/FVC), which may support the existence of sex-specific features of COPD susceptibility and severity observed in PI*ZZ patients [25].