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Updated: Aug 4, 2026
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Detection of Low Copy Number Integrated Viral DNA Formed by In Vitro Hepatitis B Infection
Published on: November 7, 2018
HBe seroconversion and HBs mutation among Japanese hepatitis B virus carriers
1Department of Internal Medicine, Division of Gastroenterology, Tohoku University School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Japan
Summary
Hepatitis B virus (HBV) genotype changes were not observed during HBe seroconversion in Japanese patients. Specific mutations in genotype C HBV, particularly at amino acid 126, may influence carrier status.
Area of Science:
- Hepatology
- Virology
- Molecular Biology
Background:
- Hepatitis B virus (HBV) genotype distribution varies geographically.
- Previous studies suggested HBV genotype shifts during seroconversion, particularly from genotype A to D in Germany.
- In Japan, genotype B HBV is more prevalent in HBeAg-negative carriers compared to genotype C.
Purpose of the Study:
- To investigate if genotype changes from C to B occur during HBe seroconversion in Japanese HBV carriers.
- To analyze mutations within the S gene of HBV during HBe seroconversion.
Main Methods:
- Analysis of 72 paired serum samples from Japanese HBV carriers before and after HBe seroconversion.
- Sequencing of the S gene (amino acids 42-164) to detect nucleotide changes and genotype.
- Identification and characterization of codon mutations.
Main Results:
- No instances of HBV genotype change (C to B) were detected during HBe seroconversion in the study cohort.
- A total of 71 codon mutations were identified, with 87.3% being non-synonymous.
- Genotype B showed no specific mutational hot spots.
- Genotype C exhibited a mutational hot spot at amino acid 126 of the S protein, with Thr126 potentially linked to asymptomatic carrier status post-seroconversion.
Conclusions:
- HBV genotype changes are not a common event during HBe seroconversion in the Japanese population.
- Specific mutations within genotype C HBV, such as at amino acid 126, may play a role in the clinical outcome of HBV infection after HBe seroconversion.
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