These results point to a novel explanation for TGF-β as a genetic modifier of CF lung disease and indicate emerging anti-fibrotic therapies under development for disease such as systemic sclerosis and idiopathic pulmonary fibrosis [16] should also be considered as interventions to diminish tissue scarring and respiratory compromise in CF. This evidence concerns the gene TGFB1 and idiopathic pulmonary fibrosis.