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A Protocol for Analyzing Hepatitis C Virus Replication
13:04

A Protocol for Analyzing Hepatitis C Virus Replication

Published on: June 26, 2014

Hepatitis C virus protease gene diversity in patients coinfected with human immunodeficiency virus

Mark A Winters1, Seth L Welles, Mark Holodniy

  • 1Division of Infectious Diseases and Geographic Medicine, Stanford University, California, USA.

Journal of Virology
|March 31, 2006
PubMed

Insights

Hepatitis C virus (HCV) protease gene variability was assessed in HIV-coinfected individuals. Significant within-patient genetic diversity was found, potentially impacting HCV protease inhibitor efficacy.

Area of Science:

  • Virology
  • Molecular Biology
  • Infectious Diseases

Background:

  • Hepatitis C virus (HCV) infection is a global health concern.
  • Coinfection with human immunodeficiency virus (HIV) complicates HCV management.
  • HCV protease inhibitors are crucial for treatment, but viral evolution can lead to resistance.

Purpose of the Study:

  • To evaluate the clonal variability of the HCV protease gene in individuals coinfected with HIV.
  • To determine if variability differs across HCV genotypes (1a, 1b, 2b, 3a).
  • To assess the implications of this variability for HCV protease inhibitor effectiveness.

Main Methods:

  • Analysis of HCV protease gene sequences from 24 HIV-coinfected patients.
  • Quantification of nucleotide and amino acid variability within and among patients.
  • Mixed-model analysis to compare variability across genotypes after adjusting for intrapatient variation.

Main Results:

  • Within-genotype nucleotide and amino acid variability ranged from 6.5–8.6% and 2.2–3.8%, respectively.
  • Significant intrapatient clonal variability was observed, up to 5.3% at the nucleotide and 5.8% at the amino acid level.
  • HCV genotype 1a exhibited significantly greater nucleotide variability compared to other genotypes (P = 0.01).

Conclusions:

  • Substantial clonal variability exists within the HCV protease gene at the patient level.
  • This intrapatient variability may influence the efficacy of HCV protease inhibitor therapies.
  • Further research is needed to understand the clinical impact of HCV genetic diversity in coinfected populations.

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