CFTR and cystic fibrosis: Cystic fibrosis (CF) is a potentially lethal genetic disease caused by bi-allelic pathogenic variants on the gene encoding the CF transmembrane conductance regulator (CFTR) protein, a cAMP-dependent chloride (Cl−) and bicarbonate (HCO3−) channel expressed at the apical membrane of various epithelial cells in the respiratory, gastrointestinal, and reproductive tracts, among others [1].