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Development of a Hepatitis B Virus Reporter System to Monitor the Early Stages of the Replication Cycle
Published on: February 1, 2017
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Epidemiologic and virologic characteristics of hepatitis B virus genotype B having the recombination with genotype C
Fuminaka Sugauchi1, Etsuro Orito, Takafumi Ichida
1Department of Internal Medicine and Molecular Science and Clinical Molecular Informative Medicine, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
Gastroenterology
|April 3, 2003
Summary
Hepatitis B virus genotype B with genotype C recombination (HBV/Ba) is common in Asia, unlike in Japan where HBV/Bj predominates. HBV/Ba carriers show higher rates of hepatitis B e antigen (HBeAg).
Area of Science:
- Hepatology
- Virology
- Genetics
Background:
- Hepatitis B virus (HBV) genotype B (HBV/B) isolates with or without recombination with genotype C (HBV/C) in the precore and core gene regions have been documented.
- These recombinations can influence viral behavior and disease presentation.
Purpose of the Study:
- To differentiate HBV/B isolates with genotype C recombination (HBV/Ba) from those without (HBV/Bj).
- To investigate the geographical distribution and clinical implications of these HBV/B subtypes.
Main Methods:
- A restriction fragment length polymorphism (RFLP) method was developed based on a single nucleotide polymorphism (SNP) at nucleotide 1838 (A in HBV/Ba vs. G in HBV/Bj).
- Genotyping of 41 HBV/Ba and 29 HBV/Bj isolates was performed.
- A case-control study compared clinical markers between HBV/Ba and HBV/Bj carriers.
Main Results:
- HBV/Bj was prevalent in Japan (93%), while HBV/Ba was found in all carriers from other Asian countries and the US.
- Hepatitis B e antigen (HBeAg) and the core promoter double mutation (T1762/A1764) were significantly more frequent in HBV/Ba carriers.
- HBeAg prevalence was notably higher in HBV/Ba carriers over 30 years old compared to HBV/Bj carriers.
Conclusions:
- HBV/B with genotype C recombination (HBV/Ba) is widespread in Asia, excluding Japan, where HBV/Bj is dominant.
- HBV/Ba infection is associated with a higher prevalence of HBeAg, suggesting potential differences in viral replication or immune response.
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