ISG expression, stratified based on IL28B genotype, is similar between G1 and G3 infected patients. PBMCs were isolated from HCV infected patients prior to them commencing IFN-α therapy and were stimulated in vitro with 1000 IU of IFN-α for 4 h. qRT-PCR was used to quantify endogenous and IFN-α stimulated expression of ISGs. ISG expression was stratified based on rs12979860 genotype and (A) endogenous and (B) IFN-α stimulated ISG expression was measured. All gene expression was normalised to expression of the internal control gene RPS15 and expressed on a log scale. Each dot represents one sample and median gene expression is shown. Data were analysed using Wilcoxon matched-pairs rank test and Mann–Whitney U-tests.