TABLE 2.

Classification of CFTR mutationsa

ClassDescriptionTranslationProcessingFunctionRegulationCommon mutations
INo CFTR proteinG542X, W1282X, R553X
IIDefective protein+++ΔF508
IIIcAMP unresponsive+++G551D, N1303K
IVcAMP responsive, reduced conductance++±+R117H, R347P
VReduced synthesis/processing±±++5T, 621 + 1 G→Tb
  • a As proposed by Wilschanski et al. (343).

  • b G to T at position +1 of intron 4, which starts at nucleotide 621.