Hepatitis B virus ; classification ; genetics ; High-Throughput Nucleotide Sequencing

Amino Acid Sequence ; Hepatitis B Surface Antigens ; classification ; genetics ; immunology ; Hepatitis B virus ; immunology ; Mutation

China ; epidemiology ; Genotype ; Hepatitis B ; epidemiology ; virology ; Hepatitis B virus ; classification ; genetics ; Humans ; Mutation ; Seroepidemiologic Studies

<b>OBJECTIVEb>To establish a sensitive, specific, simple and practicable method for identifying the two sub-genotypes (Ba and Bj) of genotype B isolates of hepatitis B virus (HBV) (HBV/ B).

<b>METHODSb>The entire nucleotide sequences of HBV/B and HBV/C were obtained from GenBank, compared and analyzed with DNAStar software. The specific primers for HBV/B (HB) and Ba (BA), Bj (BJ) were designed respectively. HB as HBV/B specific primer (sense) and HBAS-4V (designed by Japanese scientists Sugauchi et al) as a universal outer primer (antisense) were used in the first-round PCR. In the second-round PCR, HB was also used as sense primer while BA and BJ as inner primers (antisense) and they were added into a single tube for PCR reaction. The two sub-genotypes of HBV/B were identified according to the length of the PCR products. A total of 71 HBV DNA-positive serum samples were selected randomly from our laboratory, including 56 HBV/B samples identified by type-specified PCR method and 15 HBV/C samples identified by direct sequencing in preS and S Region (preS/S). All the 71 samples were detected with this semi-nested PCR method. A plasmid containing full length genomic DNA of HBV/Bj, was presented by Professor Kenji Abe as positive control of Bj. Then, the first-round PCR products of 15 HBV/B were randomly selected and sequenced directly, and their sequences were compared phylogenetically with the above known Ba and Bj sequences using Blast and DNAStar softwares to confirm the results of semi-nested PCR.

<b>RESULTSb>56 HBV/B samples were all identified as HBV/Ba by our semi-nested PCR method. 15 randomly selected PCR products were all sequenced as HBV/Ba. All of the 15 HBV/C samples were negative.

<b>CONCLUSIONb>A simple, rapid, sensitive and specific method for identifying sub-genotypes Ba and Bj was established with might be used for large-scale clinical and epidemiological studies.

Genotype ; Hepatitis B ; virology ; Hepatitis B virus ; classification ; genetics ; pathogenicity ; Humans ; Phylogeny ; Polymerase Chain Reaction ; methods

China ; Female ; Genotype ; Hepatitis B ; blood ; virology ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; classification ; genetics ; Humans ; Male ; Serotyping

China ; epidemiology ; Hepatitis B ; classification ; epidemiology ; virology ; Hepatitis B Surface Antigens ; blood ; Hepatitis B virus ; genetics ; isolation & purification ; Humans ; Mutation

<b>OBJECTIVEb>To determine the main genotype of hepatitis B virus (HBV) detected from Tibetans in China and provide basic data for hepatitis control and prevention.

<b>METHODSb>The S gene and C gene were amplified by PCR from the sera of HBsAg positive Tibetans. After sequencing, the gene sequences were analyzed and the phylogenetic trees were drawn by the software MEGA3.

<b>RESULTSb>In trees based on S gene, the sequences of most samples clustered at genotype D, while in trees based on C gene, the sequences of all samples clustered at genotype C.

<b>CONCLUSIONb>The dominant genotype of HBV detected from Tibetans in China is a C/D hybrid.

Genotype ; Hepatitis B ; blood ; epidemiology ; virology ; Hepatitis B Core Antigens ; genetics ; Hepatitis B Surface Antigens ; blood ; genetics ; Hepatitis B virus ; classification ; genetics ; immunology ; Humans ; Phylogeny ; Tibet ; epidemiology

Hepatitis B is one of the most serious global threats to human health. Phylogenetic analysis of hepatitis B virus (HBV) can reveal the evolutionary relationship between HBV sequences and thus provide a basis for the prediction and treatment of hepatitis B and other aspects. In this study, we performed sequence analyses on the HBV sequences of five clinical HBV samples and the HBV sequences retrieved from the GenBank, EMBL, and DDBJ to construct a phylogenetic tree and analyze sequence structures. The experimental results revealed that the C gene of one cloned sequence had a recombinant structure of HBV B/ C subtype. Moreover, the phylogenetic results proved the existence of a newly found subtype HBV/B6 in Xishuangbanna of Yunnan Province, China. The experimental conclusion represents certain value for phylogenetic studies of HBV in Yunnan ethnic minority groups.
DNA, Recombinant ; genetics ; Genes, Viral ; genetics ; Genotyping Techniques ; Hepatitis B virus ; classification ; genetics ; Humans ; Phylogeny

<b>OBJECTIVEb>Using PCR-RDB to establish a new method for HBV genotyping, and to survey the distribution of HBV genotypes in the Foshan area.

<b>METHODSb>Biotin-labeled primers for amplification of HBV region X (nt1550-1789) were used to amplify extracted HBV DNA. HBV was genotyped by hybridization of the PCR products with immobilized specific probes (genotype A to F) on C membrane. Color development was achieved by adding POD and TMB. A judgment was made according to color reactions. The reliability of this new method was verified by gene sequencing. 300 samples of HBV DNA-positive sera from the Foshan area were genotyped using this assay.

<b>RESULTSb>Of the 300 sera genotyped by PCR-RBD, 147 (49.0%) cases were genotype B, 136 (45.3%) were genotype C, 1 (0.3%) genotype D, and 12 (4.0%) were mixtures of genotype B and C, and 4 (1.3%) were mixtures of genotype C and D. No genotype A, E or F were found. The results of PCR-RDB genotyping were consistent with the results obtained with sequence analysis.

<b>CONCLUSIONb>This newly established HBV genotyping system proved to be sensitive, specific, precise and economic, and should be suitable for clinical practice and epidemic study. The results of HBV genotyping show that genotype B and C are the predominant genotypes in the Foshan area.

DNA, Viral ; genetics ; Female ; Genotype ; Hepatitis B ; virology ; Hepatitis B virus ; classification ; genetics ; Humans ; Male ; Oligonucleotide Array Sequence Analysis ; methods

Molecular typing was conducted according to the reported method for one HBsAg positive carrier who had a physical examination in Yunnan Province. The S gene of this HBV sample was amplified by nested PCR and the PCR products were directly sequenced. Blast searching was done on the Genbank database and the sequence were compared with the HBV reference sequences in database. The phylogenetic tree was constructed. Homology analysis of nucleotide and smino acid were performed between the sequences from the sample and the reference sequences corresponding to HBV genotype A to I. Analysis of nucleotide and amino acid identities suggested that the sample belonged to HBV genotype I. The HBV genotype I is the first reported in China.
Adult ; China ; Genotype ; Hepatitis B Surface Antigens ; genetics ; Hepatitis B virus ; classification ; genetics ; Humans ; Male ; Phylogeny ; Polymerase Chain Reaction