Correlation between a single nucleotide polymorphism (G/T at nt –88) in the Mx1 gene promoter and the response to interferon therapy for hepatitis C virus in Egyptian patients

Abstract

Interferon used in the treatment of hepatitis C virus (HCV) patients stimulates the expression of a number of host genes encoding enzymes with antiviral activities, including myxovirus resistance gene- 1 (Mx1). Mx1 gene was found to have a single nucleotide polymorphism (SNP) at position -88 in the promotor region that affect the expression of Mx 1 protein and was suggested to be associated with the response of HCV. In this study, we assessed the relation between the SNP in the Mx1 gene and the responsiveness of Egyptian HCV patients to pegylated interferon and ribavirin treatment along with other host-related and virus-related predictors of treatment outcome. We genotyped the biallelic G/T SNP in the promoter region of Mx1 gene at position -88 from the transcription start site by restriction fragment length polymorphism (RFLP) in 42 interferon treatment-naïve Egyptian patients that were treated with pegylated interferon and ribavirin. We found that Mx1 nt-88 SNP is not significantly correlated to achieving sustained virological response (SVR) after pegylated interferon alpha and ribavirin combined treatment. We conclude that Mx1 gene polymorphism at codon nt-88 cannot be considered as biological marker to potentially identify responders and non-responders of HCV patients to achieve a sustained virological response to treatment with interferon (IFN) in combination with ribavirin.

Key words: Hepatitis C virus (HCV), interferon (IFN), myxovirus resistance protein (Mx1 protein), myxovirus resistance gene-1 (Mx1 gene), single nucleotide polymorphism (SNP).