Genetic variation in NOS2A is associated with a sustained virological response to peginterferon plus ribavirin therapy for chronic hepatitis C in Taiwanese Chinese

J Med Virol. 2013 Jul;85(7):1206-14. doi: 10.1002/jmv.23598.

Abstract

This study aimed to evaluate whether genetic polymorphisms of the inducible nitric oxide synthase (iNOS) gene NOS2A could be associated with a sustained virological response (SVR) among patients infected with hepatitis C virus genotypes 1 and 2 (HCV-1 and HCV-2) who were treated with peginterferon plus ribavirin (PEG-IFNα-RBV). We analyzed the associations between SVR to PEG-IFNα-RBV therapy and two single nucleotide polymorphisms (SNPs) in NOS2A. This study included Taiwanese Chinese patients infected with either HCV-1 (n = 265) or HCV-2 (n = 195) with or without a SVR. Among the NOS2A SNPs examined, the combination of genotypes A/A and A/G of rs2248814 was inversely correlated with SVR in patients infected with HCV-1 (P = 0.0048), particularly in males (P = 0.0281). This effect was not observed in patients infected with HCV-2. The AC NOS2A haplotype comprising two SNPs (rs2248814 and rs2072324) was found to be associated with SVR, and its presence may decrease the chances for a successful outcome of treatment of patients infected with HCV-1 (P = 0.0053). HCV-1 infected patients who carried the A-C diplotype will have a lower success rate of achieving a SVR (P = 0.0117). In addition, a multivariate logistic regression model for predicting a SVR revealed that the presence of the A-C diplotype interactively affected the outcome of PEG-IFNα-RBV treatment. The presence of NOS2A SNPs and the association with SVR showed that NOS2A polymorphisms may influence the therapeutic outcomes of patients infected with HCV-1 under standard of care treatment.

Keywords: hepatitis C virus; inducible nitric oxide synthase; standard of care treatment; sustained virological response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antiviral Agents / therapeutic use*
  • Drug Therapy, Combination / methods
  • Female
  • Genotype
  • Hepatitis C, Chronic / drug therapy*
  • Hepatitis C, Chronic / virology
  • Humans
  • Interferon alpha-2
  • Interferon-alpha / therapeutic use*
  • Male
  • Middle Aged
  • Nitric Oxide Synthase Type II / genetics*
  • Polyethylene Glycols / therapeutic use*
  • Polymorphism, Single Nucleotide*
  • Recombinant Proteins / therapeutic use
  • Ribavirin / therapeutic use*
  • Taiwan
  • Treatment Outcome

Substances

  • Antiviral Agents
  • Interferon alpha-2
  • Interferon-alpha
  • Recombinant Proteins
  • Polyethylene Glycols
  • Ribavirin
  • NOS2 protein, human
  • Nitric Oxide Synthase Type II
  • peginterferon alfa-2b