Danish studies found that there was no significant association between the functional polymorphisms of the SP-B gene (rs1130866, rs2077079 and rs3024791) and lung function or hospital admissions of COPD 59, or between COPD hospitalization and EPHX1 genotypes or phenotypes in smokers or nonsmokers, respectively 28. This evidence concerns the gene EPHX1 and chronic obstructive pulmonary disease.