Neutrophil elastase, a major inflammatory neutrophil proteinase, derived from neutrophils of COPD patients is reported to exhibit resistance to AAT (alpha 1 anti trypsin) inhibition and retain ECM (extracellular matrix) binding as well as ECM protein degrading properties which might greatly accelerate lung parenchyma damage.127 COPD neutrophils also exhibit exaggerated release of histotoxic neutrophil proteases which lead to widespread tissue injury. The gene discussed is SERPINA1; the disease is chronic obstructive pulmonary disease.