Many of the airway disease associated genes are expressed by cells of the airway epithelium, including modifier loci for CF severity, such as Muc20 and Ehf, as well as risk genes shared between COPD and pulmonary fibrosis, such as Fam13a and Dsp. Overall, risk genes implicated in these airway diseases are expressed in various cell types, and our dataset enables mapping of each disease mediator to its contributing cellular source. The gene discussed is MUC20; the disease is cystic fibrosis.