title: Distribution of hepatitis delta virus genotypes in mashhad, northeast iran.
abstract: BACKGROUND
  Hepatitis delta virus (HDV) is dependent on the hepatitis B virus for transmission and propagation. Based on isolated HDV sequences from different parts of the world, at least three major different genotypes with different geographic distributions are suggested. Studies have shown that genotype 1 is the predominant genotype of HDV in different parts of Iran; however, the genotype distribution of this virus has not been identified in Mashhad, northeast Iran.
  
  
  OBJECTIVE
  This current study determines the frequency of HDV major genotypes in Mashhad, Iran.
  
  
  METHODS
  Twenty-five participants were enrolled in this study. All samples were positive for HBsAg (determined by Enzyme-linked immunosorbent assay (ELISA)) and anti-HDV. RNA extraction and cDNA synthesis was performed. Then, PCR was performed and HDV genotypes were determined by restriction fragment length polymorphism (RFLP).
  
  
  RESULTS
  Of 25 patients, 12 (48%) were positive for HDV RNA. Genotype analysis of HDV RNA revealed that the prevalence of HDV genotypes I and II was 83.3% (n = 10) and 16.7% (n = 2), respectively.
  
  
  CONCLUSIONS
  This study showed that the most prevalent genotype of HDV in Mashhad was genotype I. It was of interest that in contrast to other provinces of Iran, HDV genotype 2 was observed in Mashhad. Similar studies with larger sample sizes could provide valuable information regarding the molecular epidemiology and geographical distribution. It may also help control and prevent the spread of hepatitis D virus infections. In addition, the genotyping of HDV may predict the severity of the disease.
authors: Department of Laboratory Sciences, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Hamid
authors: H
authors: Sadeghian
authors: School of Medicine, Islamic Azad University, Mashhad Branch, Mashhad, IR Iran.
authors: Naiemeh
authors: N
authors: Varasteh
authors: Department of Internal Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Abbas
authors: A
authors: Esmaeelzadeh
authors: Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Hosein
authors: H
authors: Nomani
authors: Department of Laboratory Sciences, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Maliheh
authors: M
authors: Alimardani
authors: Department of Human Genetic, School of Medicine, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Mahdieh
authors: M
authors: Davoodnejad
authors: Department of Biostatistics, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, IR Iran.
authors: Mojtaba
authors: M
authors: Meshkat
authors: Department of Internal Medicine, School of Medicine, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Mitra
authors: M
authors: Ahadi
authors: Targeted Drug Delivery Research Center, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Samaneh
authors: S
authors: Sepahi
authors: Department of Biology, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, IR Iran.
authors: Sina
authors: S
authors: Rostami
authors: Department of Human Genetic, School of Medicine, Mashhad University of Medical Sciences, Mashhad, IR Iran.
authors: Zahra
authors: Z
authors: Meshkat
keywords: Genotype; Hepatitis Delta Virus; Polymerase Chain Reaction; Restriction Fragment Length Polymorphism