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About CF » CFTR mutations » The correlation between CFTR mutations and disease severity » Modifier genes

Modifier genes

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CF disease severity was originally thought to be only influenced by the type of CFTR mutation. It is now known that other genes interact with CFTR to modify the clinical outcome – so called ‘modifier genes’.1-3

Genetic modifiers of CF disease

Although dozens of candidate modifier genes have been identified, only a few have been substantiated in groups of more than 1000 patients with CF.1


This diagram shows some recognised genetic modifiers of CF. CFM1, cystic fibrosis modifier; HLA-II, MHC class II antigen; MBL2, mannose-binding lectin (protein C) 2; NOS1, nitric oxide synthase 1; TGFB1, transforming growth factor-a1; TNFA, tumour necrosis factor-a encoding gene. [Adapted from Bandano et al.2]
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  1. Cutting GR. Ann N Y Acad Sci 2010;1214:57–69
  2. Badano JL & Katsanis N. Nat Rev Genet 2002;3:779–89
  3. Zielenski J. Respiration 2000;67:117–33