Background: Owing to a highly variable natural course, the benefits of a successful treatment may be marginal for many hepatitis C patients. Therefore, the ability to discriminate patients with chronic hepatitis C virus (HCV) infection at risk of severe consequences, to whom more aggressive treatment strategies should be directed, would be important for clinicians.
Objective: To review the status of medical research in this area and its transferability to today's medical diagnostics.
Methods: A Medline search was conducted with the keywords hepatitis C, fibrosis, cirrhosis, polymorphism(s) and outcome. Other papers were identified from personal knowledge by the authors or reviewing the references of articles otherwise selected.
Results/conclusion: The vast majority of data were generated by a candidate-gene strategy, ending in conflicting or irreproducible results. Lack of consistent associations between specific single nucleotide polymorphisms and fibrosis severity in hepatitis C has many reasons, including small sample size, mixed ethnicity of the populations studied, and heterogeneity of outcome measures. Recently, assaying tens of thousands of single nucleotide polymorphisms in a multistage research strategy and using a combination of several different single nucleotide polymorphisms have set the stage for future, high-quality studies. This will hopefully close the gap between research and clinical applications in this area.