Genetic factors can play an important role for treatment response and disease progression in chronic viral hepatitis.
Professor Ferenci and colleagues from Austria reviewed the influence of host genetic factors on the clinical course as well as on treatment response in patients with viral hepatitis.
The research team performed a review of the literature.
A landmark genome-wide association study (GWAS) identified polymorphisms in the IL28B gene on chromosome 19 (19q13.13) associated with response to therapy with pegylated interferon-α (PEG-IFN) and ribavirin (RBV), and spontaneous viral clearance in acute hepatitis C.
The team found that IL28B genotype is associated with changes of lipid metabolism and insulin resistance.
|Some variants of the HLA-DP locus protect against progression of chronic hepatitis B infection|
|Alimentary Pharmacology & Therapeutics|
The researchers identified a further GWAS demonstrated that ITPA genetic variants protect HCV genotype 1 patients from RBV-induced anaemia.
Another polymorphism in the patatin-like phospholipase domain containing 3 (PNPLA3) is associated with hepatic steatosis.
The team noted that difficult-to-treat hepatitis C patients homozygous for GG had an up to 5-fold lower chance of viral clearance on PEG/RBV than non-GG patients.
In chronic hepatitis B patients treated with PEG-IFN several retrospective analyses of IL28B rs12980275 and rs12979860 genotypes yielded conflicting results which can be explained by the heterogeneity between the study populations.
The researchers found that some variants of the HLA-DP locus (HLA-DPA1 A allele and HLA-DPB1) protect against progression of chronic hepatitis B infection.
Professor Ferenci and colleagues conclude, "The determination of IL28B polymorphisms may be useful to individualise treatment options when using PEG/RBV based therapies for chronic hepatitis C infection."
"In contrast, so far identified genetic factors play only a minor role in chronic hepatitis B infection."