CFTR and cystic fibrosis: Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which results in altered chloride and bicarbonate secretion and the accumulation of abnormally thick mucus in the lungs and intestine, affecting more than 70,000 people worldwide (Lopes-Pacheco, 2020).