Of note, also a DNA-based protocol, especially with a limited CFTR mutation panel, does not guarantee that the required PPV of 30% is reached, as seen with the IRT/DNA protocol run in parallel in the CF-NBS centre Heidelberg (15.3%) and in the French study published 2014 (27.1%) [10,15] (Table 1). This evidence concerns the gene CFTR and cystic fibrosis.