RESUMO
BACKGROUND: Hepatitis B virus (HBV) is classified into 7 genotypes (A-G) that have distinct geographic distribution. Several studies have suggested that the HBV genotypic differences influence the severity of liver disease and clinical outcomes such that genotype C is associated with more advanced liver diseases and genotype B is associated with the earlier development of hepatocellular carcinoma. With the different genotypes of HBV reported in Shanghai, Taiwan and Japan, wetried to investigate the distribution of the HBV genotype and the utility of HBV genotyping tests in the Korea population. METHODS: A total of 51 HBV DNA positive serum from Korean hepatitis B patients were used for the genotyping. After PCR and sequencing, HBV genotypes were determined by phylogenetic analysis using the NCBI database (www.ncbi.nlm.nih.gov). RESULTS: By phylogenetic analysis in the Pre-S region, all the genotypes of HBV (100%) proved to be C. CONCLUSIONS: All patients in this study had genotype C. This result is consistent with previous studies reporting 96-100% distribution of genotype C in Korea. HBV genotyping in Korea is not informative in predicting individual variation of clinical outcome, so that it is meaningless to genotype HBV in routine laboratory genotyping.
Assuntos
Humanos , Carcinoma Hepatocelular , DNA , Genótipo , Hepatite B , Vírus da Hepatite B , Hepatite , Japão , Coreia (Geográfico) , Hepatopatias , Reação em Cadeia da Polimerase , TaiwanRESUMO
BACKGROUND: Hepatitis B virus (HBV) is classified into 7 genotypes (A-G) that have distinct geographic distribution. Several studies have suggested that the HBV genotypic differences influence the severity of liver disease and clinical outcomes such that genotype C is associated with more advanced liver diseases and genotype B is associated with the earlier development of hepatocellular carcinoma. With the different genotypes of HBV reported in Shanghai, Taiwan and Japan, wetried to investigate the distribution of the HBV genotype and the utility of HBV genotyping tests in the Korea population. METHODS: A total of 51 HBV DNA positive serum from Korean hepatitis B patients were used for the genotyping. After PCR and sequencing, HBV genotypes were determined by phylogenetic analysis using the NCBI database (www.ncbi.nlm.nih.gov). RESULTS: By phylogenetic analysis in the Pre-S region, all the genotypes of HBV (100%) proved to be C. CONCLUSIONS: All patients in this study had genotype C. This result is consistent with previous studies reporting 96-100% distribution of genotype C in Korea. HBV genotyping in Korea is not informative in predicting individual variation of clinical outcome, so that it is meaningless to genotype HBV in routine laboratory genotyping.
Assuntos
Humanos , Carcinoma Hepatocelular , DNA , Genótipo , Hepatite B , Vírus da Hepatite B , Hepatite , Japão , Coreia (Geográfico) , Hepatopatias , Reação em Cadeia da Polimerase , TaiwanRESUMO
BACKGROUND: YMDD motif variants of the hepatitis B virus (HBV) emerge in some chronic hepatitis B patients after prolonged lamivudine treatment. HBV DNA breakthrough may be accompanied by the emergence of YMDD variants. The detection of YMDD motif variants will be necessary since Adefovir dipivoxil was recently approved to be an effective treatment for lamivudine-resistant patients. METHODS: Samples were chosen from twenty-one patients who experienced the DNA breakthrough after an undetectable HBV DNA period by HBV DNA hybrid-capture assay. We tested the samples of each stage for detection of YMDD motif variants by a sequencing method using Accu-Typer(TM) HBV YMDD typing Kit (DNA Link, Seoul, Korea) and ABI PRISM 3700 DNA Analyzer. RESULTS: All 17 samples that were collected before treatment had the wild-type YMDD motif. Of 20 samples amplified, which were from the undetectable HBV DNA period, three (15%) samples showed YMDD mutation. After DNA breakthrough, YMDD mutants were detected in 13 (63%) of 21 samples (YIDD 8 cases, YVDD 5 cases). CONCLUSION: We could reconfirmed that YMDD motif variants were remarkably related to the lamivudin resistance. YMDD motif variants; however, were not detected in one-third of the lamivudine resistance. The sequencing method of our study would be useful in providing the neighboring nucleotide information other than the YMDD motif in patients experiencing DNA breakthrough.