title: Molecular characterization of hepatitis B virus isolates from Zimbabwean blood donors.
abstract: Hepatitis B virus (HBV) is endemic in Africa, being hyperendemic in sub-Saharan Africa. Genotypes A, D, and E circulate in Africa, showing a distinct geographical distribution. The aim of the present study was to determine the HBV genotype distribution in blood donors from different geographical locations in Zimbabwe. Using a restriction fragment polymorphism assay, sequencing of the basic core promoter/precore region and of the complete S open reading frame showed that 29 HBV isolates from geographically distinct regions belong to subgenotype A1. The complete genome of two of these Zimbabwean HBV isolates was sequenced. Forty-four percent of the Zimbabwean HBV isolates (11/23) were characterized by a G1862C missense mutation, which causes a Val to Leu amino acid substitution at position 17 of the precore region. The majority of Zimbabwean HBV isolates clustered with a number of South African HBV isolates, with which they shared characteristic amino acids in the preS1, preS2, and polymerase spacer regions. The wide distribution of subgenotype in Africa, as well as the high intragroup divergence and the geographical clustering of the African and Asian subgenotype A1 HBV isolates indicate that this subgenotype has a long period of endemicity in these regions.
authors.affiliation: Hepatitis Virus Diversity Research Programme (formerly MRC/CANSA/University Molecular Hepatology Research Unit), Faculty of Health Sciences, Department of Internal Medicine, University of the Witwatersrand, Parktown, Johannesburg, South Africa.
authors.forename: Zandiswa
authors.initials: Z
authors.lastname: Gulube
authors.forename: Michael
authors.initials: M
authors.lastname: Chirara
authors.forename: Michael
authors.initials: M
authors.lastname: Kew
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Masashi
authors.initials: M
authors.lastname: Mizokami
authors.forename: Anna
authors.initials: A
authors.lastname: Kramvis
mesh_terms: D000293:Adolescent; D000328:Adult; D001782:Blood Donors; D005260:Female; D016679:Genome, Viral; D006509:Hepatitis B / Q000453:epidemiology / Q000821:virology*; D006512:Hepatitis B Core Antigens / Q000235:genetics; D006514:Hepatitis B Surface Antigens / Q000235:genetics; D006515:Hepatitis B virus / Q000145:classification / Q000235:genetics*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D016366:Open Reading Frames / Q000235:genetics; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D011401:Promoter Regions, Genetic / Q000235:genetics; D015030:Zimbabwe / Q000453:epidemiology
chemical_list: D006512:Hepatitis B Core Antigens; D006514:Hepatitis B Surface Antigens