INSERM, UMR773, Team «Viral hepatitis», Centre de Recherche Bichat Beaujon, BP 416, F-75018, Paris, France; Université Denis Diderot Paris 7, site Bichat, BP 416, F-75018, Paris, France; Service d'Hépatologie, PMAD Hôpital Beaujon, 100 Bd du Général Leclerc, Clichy la Garenne, 92110 Clichy Cedex, France; Laboratory of Excellence Labex INFLAMEX, PRES Paris Sorbonne Cité, France.
HCV infection is a global health problem that affects 170 million people worldwide. The severity of the disease varies from asymptomatic chronic infection to cirrhosis and hepatocellular carcinoma (HCC). Recently, the standard of care for genotype 1 patients has greatly improved with the addition of protease inhibitors (telaprevir or boceprevir) to pegylated interferon (PEG-IFN) and ribavirin (RBV). The prediction of the progression of fibrosis and the response to antiviral treatment are two major issues in the management of patients with chronic hepatitis C. Differential expression of mRNAs was first analyzed for both the progression of fibrosis and treatment response. Specific polymorphisms, associated with either fibrosis or viral response, were identified thanks to major improvements in genome scanning technologies. Since 2009, several independent Genome wide association studies (GWAS) have reported an association between genetic polymorphisms within the IL28B promoter and both natural and treatment-induced clearance in genotype 1 infected patients. These different studies showed the strong association and the importance of IL28B polymorphisms in the treatment response. Combining the different genetic factors could improve their predictive value and help identify patients at a high risk of progression of fibrosis as well as those with a lower chance of responding to treatment. The aim of this review was to discuss the genomic factors (mRNAs, miRNAs and SNPs) and HCV infection with clinical implications for either the progression of fibrosis or treatment response. Recent findings on the IL28B polymorphism and its application in clinical practice will also be discussed.