CFTR and cystic fibrosis: In individuals presenting with a positive newborn bloodspot screening (NBS), i.e., with an immunoreactive trypsinogen above the cut-off, clinical features consistent with CF, or a positive family history, a diagnosis of CF can be made if the sweat chloride (SC) value is ≥60 mmol/L or in presence of 2 CFTR causing variants [2].