title: Full genome analysis of hepatitis B virus genotype E strains from South-Western Africa and Madagascar reveals low genetic variability.
abstract: The eight genotypes of hepatitis B virus (HBV), A-H, have a characteristic geographical distribution. The high prevalence of genotype E within a wide expanse of Africa makes it important to characterize this genotype. Although the preS/S region of a large number of genotype E isolates has been sequenced, to date only eight complete genotype E genomes have been published. The aim of this study, therefore, was to sequence and characterize the complete genome of genotype E isolates obtained from geographically distinct regions in Africa, including Namibia, Angola, and Madagascar. The nine newly sequenced genotype E isolates were closely related with an intra-group nucleotide divergence of 1.2%, reflecting their close geographical origin. All genotype E strains have the same characteristics, an in-frame deletion of three nucleotides (one amino acid) in the 5' pre-S1, a signature pattern of amino acids in the pre-S1 region and the serological subtype ayw4. In addition, we have identified another unique attribute of genotype E strains, the introduction of another start codon Met(83) in the pre-S1 region that may result in the translation of an elongated middle hepatitis B surface protein (MHBs).
authors: MRC/University Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand, Johannesburg, South Africa. kramvisa@medicine.wits.ac.za
authors: Anna
authors: A
authors: Kramvis
authors: Karin
authors: K
authors: Restorp
authors: Heléne
authors: H
authors: Norder
authors: Johan F
authors: JF
authors: Botha
authors: Lars O
authors: LO
authors: Magnius
authors: Michael C
authors: MC
authors: Kew
mesh_terms: D000328:Adult; D000353:Africa, Southern / Q000453:epidemiology; D002648:Child; D005260:Female; D014644:Genetic Variation / Q000235:genetics*; D016679:Genome, Viral; D005838:Genotype; D006509:Hepatitis B / Q000453:epidemiology / Q000821:virology; D006513:Hepatitis B e Antigens / Q000097:blood / Q000235:genetics*; D006515:Hepatitis B virus / Q000145:classification / Q000235:genetics*; D006801:Humans; D008270:Madagascar / Q000453:epidemiology; D008297:Male; D010802:Phylogeny; D017422:Sequence Analysis, DNA
chemical_list: D006513:Hepatitis B e Antigens