CFTR and cystic fibrosis: Full intronic sequencing should be selectively performed in people with CRMS/CFSPID who demonstrate evidence of potential CFTR dysfunction (eg, sweat [Cl−] of 30–59 mmol/L), or individuals for whom the clinical suspicion of CF development is high and who possess only 1 previously identified causal variant after full sequence and del/dup is provided (see Supplemental Information for further discussion).