Among animals, pig airways share many features with human airways [31] and CF pigs, both CFTR-/-[32] and CFTRΔF508/ΔF508[33] have now been generated and shown to share many features of CF organ-level disease [34], [35], [36], [37], including a defect in tracheal host defense against bacterial infections [37], and defective tracheal gland secretion [38]. The gene discussed is CFTR; the disease is cystic fibrosis.