Novel subtypes (subgenotypes) of hepatitis B virus genotypes B and C among chronic liver disease patients in the Philippines.
Several hepatitis B virus (HBV) subtypes (subgenotypes), HBV/Aa (A1 : Asia/Africa), Ae (A2 : Europe), Bj (B1 : Japan) and Ba (B2 : Asia), have been reported with respect to clinical differences between patients infected with these subtypes (subgenotypes). HBV genotype distribution among patients with chronic liver diseases was investigated in the Philippines, where such studies have not been carried out previously. One hundred sera were obtained from such patients, consisting of 32 chronic hepatitis (CH), 37 cirrhosis and 31 hepatocellular carcinoma (HCC) patients. Nine complete genomes and 100 core promoter/precore genes of HBV were sequenced directly. Phylogenetic analyses revealed 51 HBV/A (Aa/A1), 22 HBV/B and 27 HBV/C strains. Interestingly, most HBV/C strains in the Philippines formed a specific cluster distinct from previous HBV/C strains (C1-4), indicating a novel subtype (subgenotype), HBV/C5. Moreover, most HBV/B strains fell within the specific cluster of the HBV/B subtype (subgenotype) B5, with viral characteristics of HBV/Ba (B2) carrying a recombination with HBV/C over the precore and core genes. Of the three genotypes, HBV/B and HBV/C were significantly more prevalent than HBV/A in cirrhosis and HCC patients (P<0.02). The prevalence of the core promoter mutations T1762/A1764 was higher in HCC patients with HBV/B and HBV/C. Multivariate analysis indicated that age [odds ratio (OR) 3.43; 95 % confidence interval (CI) 1.04-11.36; P=0.044] and the core promoter mutation (OR 14.08; 95% CI 3.62-4.74; P<0.001) were significant factors for HCC development. In conclusion, novel HBV subtypes (subgenotypes) C5 and B5 are prevalent in the Philippines, as well as HBV/Aa (A1).
Sakamoto
Tomoyuki
T
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.|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.
Orito
Etsuro
E
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Co
Jonard
J
Section of Gastroenterology, University of Santo Tomas, Manila, Philippines.
Clavio
Joseph
J
Section of Gastroenterology, University of Santo Tomas, Manila, Philippines.
Sugauchi
Fuminaka
F
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Ito
Kiyoaki
K
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Ozasa
Atsushi
A
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Quino
Alvin
A
Section of Gastroenterology, University of Santo Tomas, Manila, Philippines.
Ueda
Ryuzo
R
Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
Sollano
Jose
J
Section of Gastroenterology, University of Santo Tomas, Manila, Philippines.
Mizokami
Masashi
M
Department of Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical Sciences, Kawasumi, Mizuho, Nagoya 467-8601, Japan.
D006528:Carcinoma, Hepatocellular / Q000821:virology; D004742:Enhancer Elements, Genetic; D019143:Evolution, Molecular; D016679:Genome, Viral; D005838:Genotype; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000821:virology*; D006801:Humans; D008103:Liver Cirrhosis / Q000821:virology; D008113:Liver Neoplasms / Q000821:virology; D008969:Molecular Sequence Data; D009154:Mutation; D010679:Philippines; D010802:Phylogeny; D011401:Promoter Regions, Genetic; D014758:Viral Core Proteins / Q000235:genetics
D014758:Viral Core Proteins