PRJDB2979 HCV NS5A sequencing Recent advances in interferon-free treatment could lead to the eradication of HCV from patients infected with HCV. One of the direct-acting anti-viral agents, HCV NS5A inhibitor is available for these combination therapies. However, naturally occurring resistance-associated variants (RAVs) to HCV NS5A inhibitors in treatment-na?ve patients with chronic hepatitis C are still unknown. Here, we performed ultra-deep sequencing and analyzed previously reported RAVs in a total 132 HCV genotype 1b-infected Japanese patients who had never used HCV NS5A inhibitors. We also performed direct-sequencing by Sanger method and examined the differences between the results of the two methods. HCV NS5A sequencing bioproject PRJDB2979 PRJDB2979 true Recent advances in interferon-free treatment could lead to the eradication of HCV from patients infected with HCV. One of the direct-acting anti-viral agents, HCV NS5A inhibitor is available for these combination therapies. However, naturally occurring resistance-associated variants (RAVs) to HCV NS5A inhibitors in treatment-na?ve patients with chronic hepatitis C are still unknown. Here, we performed ultra-deep sequencing and analyzed previously reported RAVs in a total 132 HCV genotype 1b-infected Japanese patients who had never used HCV NS5A inhibitors. We also performed direct-sequencing by Sanger method and examined the differences between the results of the two methods.