title: Prevalence of HBV core promoter/precore/core mutations in Gambian chronic carriers.
abstract: One hundred forty-two precore/core sequences were obtained from Gambian chronic hepatitis B virus (HBV) carriers and the predominant variants defined. The two point mutations, from A to T and G to A at nt positions 1762 and 1764 in the basic core promoter region, were found in only 7/99 (7%) of the samples where this region was sequenced. These mutations were found in both HBeAg-positive and -negative patients. The precore stop-codon mutation at nt position 1896 was found in 14/51 (27%) of HBeAg-negative samples, which is a lower prevalence rate in comparison with other parts of the world with high carrier rates. In HBeAg-positive patients the core amino acid sequences were conserved, but after seroconversion to anti-HBe significantly more changes were apparent. Several of the amino acid substitutions found have been described previously been in wild-type viruses of other genotypes.
authors.affiliation: Department of Medicine A, Imperial College School of Medicine, London, United Kingdom.
authors.forename: U
authors.initials: U
authors.lastname: Dumpis
authors.forename: M
authors.initials: M
authors.lastname: Mendy
authors.forename: A
authors.initials: A
authors.lastname: Hill
authors.forename: M
authors.initials: M
authors.lastname: Thursz
authors.forename: A
authors.initials: A
authors.lastname: Hall
authors.forename: H
authors.initials: H
authors.lastname: Whittle
authors.forename: P
authors.initials: P
authors.lastname: Karayiannis
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D002353:Carrier State / Q000453:epidemiology / Q000821:virology*; D003001:Cloning, Molecular; D018388:Codon, Terminator; D005714:Gambia / Q000453:epidemiology; D005814:Genes, Viral; D006513:Hepatitis B e Antigens / Q000032:analysis; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000453:epidemiology / Q000276:immunology / Q000821:virology*; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic; D014758:Viral Core Proteins / Q000235:genetics*
chemical_list: D018388:Codon, Terminator; D006513:Hepatitis B e Antigens; D014758:Viral Core Proteins