This is a multicenter, observational/non-interventional, cross-sectional study to describe the genetic diversity of and to identify the natural polymorphisms in HCV NS3/4a protease and NS5A protein of hepatitis C virus in Brazilian participants with chronic HCV infection. Brazilian participants with Genotype 1 HCV infection treatment naive participants or previously failed to double therapy (Peg-interferon-α and Ribavirin) will be included in the trial and will constitute the trial population.