Which of the following mutations leads to cystic fibrosis?
Cystic fibrosis is autosomal recessive disorder due to CFTR ABCC7 mutations at chromosome 7q31.2 with more than 2000 variants catalogued in CFTR2 database. F508del deletion of phenylalanine 508 in NBD1 causes misfolding, endoplasmic reticulum retention, proteasomal degradation and minimal surface expression, representing class II trafficking defect. G551D missense in NBD1 signature motif impairs ATP-dependent gating though protein reaches membrane, class III gating defect. R117H in transmembrane domain reduces conductance, class IV. G542X nonsense truncates protein, class I no synthesis. Compo
Ref: Cutting, Nat Rev Genet 2015, Cystic fibrosis genetics; CFTR2 database, cff.org.
