Heterozygous beta-globin gene mutations as a risk factor for iron accumulation and liver fibrosis in chronic hepatitis C

Gut. 2007 May;56(5):693-8. doi: 10.1136/gut.2006.106641. Epub 2006 Nov 29.

Abstract

Background: Iron accumulation is a well-known risk factor for the progression of chronic hepatitis C (CHC) to fibrosis. However, the profibrogenic role of the genes controlling iron homeostasis is still controversial.

Aim: To evaluate the relative role of haemachromatosis (HFE), ferroportin and beta-globin gene mutations in promoting iron accumulation and fibrosis in patients with CHC.

Methods: Genetic analysis was performed together with the assessment of hepatic iron content and histology in 100 consecutive HIV-antibody and hepatitis B surface antigen-negative patients with biopsy-proven CHC.

Results: Among the patients investigated, 12 were heterozygous for various beta-globin gene mutations (39[C-->T], IVS1.1[G-->A], 22 7 bp deletion and IVS1.6[T-->C]) and 29 carried HFE (C282Y, H63D and S65C) gene mutations. One further patient was heterozygous for both HFE (H63D) and beta-globin (39[C-->T]) variants, whereas 58 had the wild-type alleles of both the genes. Hepatic iron concentration (HIC) and hepatic stainable iron were significantly higher (p<0.05) in patients with CHC carrying beta-globin mutations than in those with HFE mutations or the wild-type alleles. Multivariate analysis confirmed that the presence of beta-globin mutations was independently associated with both HIC (p = 0.008) and hepatic-stainable iron (odds ratio (OR) 6.11; 95% CI 1.56 to 23.92; p = 0.009). Moderate/severe fibrosis or cirrhosis (Ishak's score >2) was observed in 48 of 100 patients. Logistic regression demonstrated that age (OR 1.05; 95% CI 1.02 to 1.09; p<0.005) and beta-globin mutations (OR 4.99; 95% CI 1.22 to 20.3; p = 0.025) were independent predictors of the severity of fibrosis.

Conclusions: Heterozygosis for beta-globin mutations is a novel risk factor for both hepatic iron accumulation and the progression to fibrosis in patients with CHC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • DNA Mutational Analysis / methods
  • Disease Progression
  • Female
  • Genetic Predisposition to Disease
  • Globins / genetics*
  • Hemochromatosis / complications
  • Hemochromatosis / genetics
  • Hepatitis C, Chronic / complications*
  • Hepatitis C, Chronic / pathology
  • Heterozygote
  • Humans
  • Iron / metabolism
  • Iron Overload / genetics*
  • Iron Overload / pathology
  • Iron Overload / virology
  • Liver / metabolism
  • Liver Cirrhosis / genetics*
  • Liver Cirrhosis / pathology
  • Liver Cirrhosis / virology
  • Male
  • Middle Aged
  • Mutation*
  • Risk Factors

Substances

  • Globins
  • Iron