Cystic fibrosis is a life-shortening, autosomal recessive disease caused by variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene that affects more than 92 000 individuals globally.1,2 There are over 2000 CFTR variants, although F508del is the most common variant in tested populations with cystic fibrosis to date, and allelic frequency varies across geographical regions. This evidence concerns the gene CFTR and cystic fibrosis.