Combination of ENaC and CFTR mutations may predispose to cystic fibrosis-like disease

To the Editors: The epithelial sodium channel (ENaC) is part of the complex protein cystic fibrosis transmembrane conductance regulator (CFTR)-interactome that plays a key role in the composition of the airway surface liquid and the mucociliary clearance in the airways. We have recently screened ENaC beta and gamma genes in 55 patients with diffuse bronchiectasis and with only one or no CFTR mutation/variant and showed that eight (15%) patients carried at least one missense mutation in these ENaC genes 1. Azad et al. 2 have also investigated the frequency of ENaC mutations in ENaC alpha, beta and gamma genes in a cohort of 76 patients with cystic fibrosis (CF)-like disease and with only one or no mutation in the CFTR gene. They found a significant increase in missense mutations or variants in patients (15.3%) compared with controls (8.9%) 2. Moreover, a variant in …