Numerous reports link a dysregulation of the gel-forming mucin MUC5B in human lung diseases like asthma, cystic fibrosis, diffuse panbronchiolitis and familial and sporadic and interstitial pneumonia idiopathic pulmonary fibrosis (Fahy and Dickey, 2010; Kamio et al., 2005; Rose and Voynow, 2006; Seibold et al., 2011; Zhang et al., 2011). The gene discussed is MUC5AC; the disease is cystic fibrosis.