title: Hepatitis B genotypes/subgenotypes and MHR variants among Moroccan chronic carriers.
abstract: OBJECTIVE
  The aim of this study was to determine the prevalence of Hepatitis B Virus (HBV) genotypes, subgenotypes, HBV surface antigen (HBsAg) subtypes and naturally occurring mutations in Major Hydrophilic region (MHR) of HBsAg among Moroccan patients with chronic HBV infection.
  
  
  METHODS
  The study included 200 patients chronically infected with HBV. The HBV genotypes, subgenotypes, HBsAg subtypes and MHR variants were determined by direct sequencing of the HBV surface (S) gene and phylogenetic analysis.
  
  
  RESULTS
  The S gene was successfully amplified in 134 patients. The mean age was 40.6 ± 12.2 years. Genotype D was predominant (90%, 120/134) and genotype A was less frequent (10%, 14/134). Genotype D strains belonged to subgenotypes D7 (70.8%, 85/120), D1 (25.8%, 31/120) and D2 (0.9%, 1/120). Three strains (2.5%) could not be classified in any subgenotype of genotype D. All genotype A strains belonged to subgenotype A2. HBsAg subtypes found were ayw2 (82.1%, 110/134), adw2 (10.4%, 14/134), ayw3 (3%, 4/134) and ayw4 (3%, 4/134). The global prevalence of MHR variants was 15% (20/134) with substitution P120T/S the most frequent (3.7%, 5/134). The occurrence of MHR variants was significantly associated with advancing age (>40 years) (p = 0.003) and independent of sex, HBeAg status, viral load, genotype, subgenotype and HBsAg subtype.
  
  
  CONCLUSIONS
  This study provides the first description of predominance of HBV subgenotype D7/subtype ayw2 among Moroccan HBV chronic carriers. It also showed a significant prevalence of naturally occurring MHR variants in Morocco.
authors.affiliation: Laboratoire des Hépatites Virales, Institut Pasteur du Maroc, Casablanca, Morocco.
authors.forename: Bouchra
authors.initials: B
authors.lastname: Kitab
authors.forename: Abdellah Essaid
authors.initials: AE
authors.lastname: El Feydi
authors.forename: Rajaa
authors.initials: R
authors.lastname: Afifi
authors.forename: Omar
authors.initials: O
authors.lastname: Derdabi
authors.forename: Younes
authors.initials: Y
authors.lastname: Cherradi
authors.forename: Mustapha
authors.initials: M
authors.lastname: Benazzouz
authors.forename: Khadija
authors.initials: K
authors.lastname: Rebbani
authors.forename: Ikram
authors.initials: I
authors.lastname: Brahim
authors.forename: Hanane
authors.initials: H
authors.lastname: Salih Alj
authors.forename: Fabien
authors.initials: F
authors.lastname: Zoulim
authors.forename: Christian
authors.initials: C
authors.lastname: Trepo
authors.forename: Isabelle
authors.initials: I
authors.lastname: Chemin
authors.forename: Sayeh
authors.initials: S
authors.lastname: Ezzikouri
authors.forename: Soumaya
authors.initials: S
authors.lastname: Benjelloun
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002353:Carrier State / Q000453:epidemiology* / Q000821:virology*; D017931:DNA Primers; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006514:Hepatitis B Surface Antigens / Q000235:genetics; D006515:Hepatitis B virus / Q000145:classification / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000453:epidemiology* / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009018:Morocco / Q000453:epidemiology; D009154:Mutation; D010802:Phylogeny; D017421:Sequence Analysis; D055815:Young Adult
chemical_list: D017931:DNA Primers; D006514:Hepatitis B Surface Antigens