We focused on the signature protein of the lung, elastin, degraded by neutrophil elastase [50], degradation of the main component of lung interstitial matrix, type I collagen, and remodeling of type VI collagen, found at the interface of the basement membrane and interstitial matrix [37], which is disrupted during progression of COPD [35]. The gene discussed is ELN; the disease is chronic obstructive pulmonary disease.