A new subtype (subgenotype) Ac (A3) of hepatitis B virus and recombination between genotypes A and E in Cameroon.
Blood samples (n=544) from two different populations (Pygmies and Bantus) in Cameroon, West Africa, were analysed. Serological tests indicated that the anti-hepatitis C virus (HCV) prevalence in Bantus (20.3 %) was higher than that in Pygmies (2.3 %, P<0.0001), whereas the distribution of hepatitis B virus (HBV) serological markers was equally high in both populations: in total, 9.4, 17.3 and 86.8 % for HBsAg, anti-HBs and anti-HBc, respectively. HBV genotype A (HBV/A) and HBV/E were predominant (43.5 % each) in both populations, and HBV/D was found in a minority (13 %). The preS/S region was sequenced in nine cases (five HBV/A and four HBV/E) and the complete genome in six cases (four HBV/A and two HBV/E). Subsequent phylogenetic analysis revealed that the HBV/A strains were distinct from the subtypes (subgenotypes) described previously, Ae (A2) and Aa (A1), and in the preS/S region they clustered with previously reported sequences from Cameroon. Based on the nucleotide difference from Aa (A1) and Ae (A2), more than 4 % in the complete genome, the Cameroonian strains were suggested to represent a new subtype (subgenotype), designated HBV/Ac (A3). A high (3.9 %) nucleotide divergence in HBV/Ac (A3) strains suggested that the subtype (subgenotype) has a long natural history in the population of Cameroon. One of the HBV/Ac (A3) strains was found to be a recombinant with an HBV/E-specific sequence in the polymerase reverse transcriptase domain. Further cohort studies will be required to assess detailed epidemiological, virological and clinical characteristics of HBV/Ac (A3), as well as its recombinant form.
Kurbanov
Fuat
F
Department of Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Tanaka
Yasuhito
Y
Department of Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Fujiwara
Kei
K
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Sugauchi
Fuminaka
F
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Mbanya
Dora
D
Department of Hematology, Faculty of Medicine and Biomedical Sciences, University of Yaounde, Yaounde BP1937, Cameroon.
Zekeng
Leopold
L
Department of Hematology, Faculty of Medicine and Biomedical Sciences, University of Yaounde, Yaounde BP1937, Cameroon.
Ndembi
Nicaise
N
Department of Hematology, Faculty of Medicine and Biomedical Sciences, University of Yaounde, Yaounde BP1937, Cameroon.
Ngansop
Charlotte
C
Department of Hematology, Faculty of Medicine and Biomedical Sciences, University of Yaounde, Yaounde BP1937, Cameroon.
Kaptue
Lazare
L
Department of Hematology, Faculty of Medicine and Biomedical Sciences, University of Yaounde, Yaounde BP1937, Cameroon.
Miura
Tomoyuki
T
Laboratory of Primate Mode, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan.
Ido
Eiji
E
Laboratory of Viral Pathogenesis, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan.
Hayami
Masanori
M
Laboratory of Viral Pathogenesis, Institute for Virus Research, Kyoto University, Kyoto 606-8507, Japan.
Ichimura
Hiroshi
H
Department of Viral Infection and International Health, Graduate School of Medical Science, Kanazawa University, Kanazawa, Ishikawa 920-8640, Japan.
Mizokami
Masashi
M
Department of Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
D000328:Adult; D001483:Base Sequence; D002163:Cameroon / Q000453:epidemiology / Q000208:ethnology; D004279:DNA, Viral / Q000032:analysis; D005006:Ethnicity; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006509:Hepatitis B / Q000453:epidemiology* / Q000208:ethnology* / Q000821:virology; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology / Q000208:ethnology / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010802:Phylogeny; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA
D004279:DNA, Viral