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Cystic fibrosis classification

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Shaghayegh Habibi, M.D.[2]

Overview

Overview

Cystic fibrosis may be classified according to CFTR protein function abnormality into 6 classes and includes lack of production (class 1), failure to reach the site of action due to misfolding (class 2), defects in gating (class 3), reduced ion conductance (class 4), abnormally low channel numbers (class 5), and decreased half-life (class 6). Cystic fibrosis classes 1,2 and 3 are the most commonly associated with pancreatic insufficiency.

Classification

Classification

Cystic fibrosis may be classified according to CFTR mutation type:[1][2][3]

Cystic fibrosis classification according to CFTR protein function abnormality
Class Type of abnormality Features
Class 1 Total or partial lack of production of a functional CFTR
Class 2 Failure to reach the site of action on the cell surface

(due to misfolding of the protein)

Class 3 Defects in gating

(fail to open in response to intracellular signal)

Class 4 Reduced ion conductance
Class 5 Abnormally low channel numbers

(splicing mutations resulting in reduced amounts of CFTR protein)

Class 6 Decreased half-life
References

References

  1. Burney TJ, Davies JC (2012). “Gene therapy for the treatment of cystic fibrosis”. Appl Clin Genet. 5: 29–36. doi:10.2147/TACG.S8873. PMC 3681190. PMID 23776378.
  2. Ratjen F, Döring G (2003). “Cystic fibrosis”. Lancet. 361 (9358): 681–9. doi:10.1016/S0140-6736(03)12567-6. PMID 12606185.
  3. Edmondson C, Davies JC (2016). “Current and future treatment options for cystic fibrosis lung disease: latest evidence and clinical implications”. Ther Adv Chronic Dis. 7 (3): 170–83. doi:10.1177/2040622316641352. PMC 4907071. PMID 27347364.

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