Association of a single nucleotide polymorphism near the interleukin-28B gene with response to hepatitis C therapy in Asian patients

J Gastroenterol Hepatol. 2011 Sep;26(9):1374-9. doi: 10.1111/j.1440-1746.2011.06744.x.

Abstract

Background and aims: A single nucleotide polymorphism near the interleukin-28B (IL28B) gene has been shown to predict hepatitis C virus (HCV) treatment response. We aim to determine the role of the IL28B genotype in Asian patients.

Methods: A total of 118 patients (all Korean, 55 patients with genotype 1 infection and 63 patients with genotype 2 infection) were consecutively enrolled and analyzed.

Results: The sustained virological response (SVR) rate was 74% (87/118), while 26 patients (22%) relapsed and five patients were non-responders (4%). For rs8099917, the frequencies of major homozygotes (TT), heterozygotes (GT), and minor homozygotes (GG) were 0.85, 0.14 and 0.01, respectively. Of the 55 patients with HCV genotype 1 infection, the SVR rate was 67% and 44% (P = 0.19) and the non-response rate was 2% and 22% (P = 0.015) for the major allele and minor or hetero allele, respectively. Of the 63 patients with HCV genotype 2 infection, the SVR rate was 80% and 100% (P = 0.13) and the non-response rate was 4% and 0% (P = 0.55) for major allele and hetero allele, respectively.

Conclusions: The IL28B genotype may help identify non-responding patients in HCV genotype 1, but not in HCV genotype 2. Because of the high frequency of favorable alleles and the low frequency of non-response, the IL28B polymorphism may play a smaller role in Asian patients.

MeSH terms

  • Aged
  • Analysis of Variance
  • Antiviral Agents / therapeutic use*
  • Asian People / genetics*
  • Chi-Square Distribution
  • Drug Therapy, Combination
  • Female
  • Gene Frequency
  • Hepacivirus / genetics
  • Hepatitis C / diagnosis
  • Hepatitis C / drug therapy*
  • Hepatitis C / ethnology
  • Hepatitis C / genetics*
  • Heterozygote
  • Homozygote
  • Humans
  • Interferon-alpha / therapeutic use*
  • Interferons
  • Interleukins / genetics*
  • Logistic Models
  • Male
  • Middle Aged
  • Pharmacogenetics
  • Phenotype
  • Polyethylene Glycols / therapeutic use*
  • Polymorphism, Single Nucleotide*
  • Prospective Studies
  • RNA, Viral / blood
  • Recombinant Proteins / therapeutic use
  • Recurrence
  • Republic of Korea / epidemiology
  • Ribavirin / therapeutic use*
  • Time Factors
  • Treatment Outcome
  • Viral Load

Substances

  • Antiviral Agents
  • interferon-lambda, human
  • Interferon-alpha
  • Interleukins
  • RNA, Viral
  • Recombinant Proteins
  • Polyethylene Glycols
  • Ribavirin
  • Interferons
  • peginterferon alfa-2a