Although CFTR-mediated HCO3− secretion is defective in CF epithelia (Smith and Welsh, 1992; Choi et al., 2001) and plays a role in ASL acidosis of neonates with CF (Abou Alaiwa et al., 2014a; Abou Alaiwa et al., 2018), it remains unclear whether abnormalities resulting from ASL acidosis in CF neonates would be the major factor causing later progressive deteriorations in the lung function of children and adult patients. Here, CFTR is linked to cystic fibrosis.