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About CF » CFTR mutations » Classification of CFTR mutations

Classification of CFTR mutations

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Mutations in the CFTR gene can be classified into six classes according to the mechanism by which they disrupt the synthesis, traffic and function of CFTR.1,2 Click on the hotspots below to find out more.

Class I

Lack of CFTR synthesis

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Class II

Defective protein processing

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Class III

Defective channel regulation or channel gating

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Class IV

Defective chloride conductance

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Class V

Reduced amount of CFTR protein (e.g. alternative splicing)

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Class VI

Increased turnover of CFTR channel at the cell surface

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Click here to see an enlarged image that summarises the overall impact of CFTR mutations, which ultimately influence the function or quantity of CFTR protein.

  1. MacDonald KD et al. Paediatr Drugs 2007;9:1–10
  2. Welsh MJ et al. Cystic fibrosis. Valle D et al (Eds). OMMBID. The McGraw-Hill Companies Inc. Part 21, chap 201, 2004