Further, we speculate that Hfe may be implicated in bacterial host defense, as well as acute and chronic neutrophilic inflammatory processes of the lung in subjects without HH, and may thus serve as a novel target for anti-infective and anti-inflammatory therapies for common lung diseases including pneumonia, acute respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD) and cystic fibrosis. The gene discussed is HFE; the disease is susceptibility to pneumonia measurement.