A negative correlation between FEV1 and the ratio of activated eosinophils to total eosinophils in endobronchial biopsies from subjects with COPD was demonstrated [21], and a similar negative correlation between FEV1 and sputum eosinophils and eosinophil cationic protein (ECP) was found [2]. This evidence concerns the gene RNASE3 and chronic obstructive pulmonary disease.