Identification of hepatitis B virus genotype I in Thailand

J Med Virol. 2019 Apr;91(4):717-721. doi: 10.1002/jmv.25346. Epub 2018 Nov 8.


The rare hepatitis B virus genotype I (HBV-I) classification includes complex A/G/C/U recombinants identified amongst the individuals from China, India, Laos, and Vietnam. Herein we report the first HBV-I specimen from Thailand, with detectable HBsAg despite a 10-amino-acid truncation. This HBV-I genome has a similar recombinant pattern to reference strains, including a C region that branches basal to references, suggesting a premodern era recombination event gave rise to HBV-I. With an average sequence divergence from other genotypes ranging from 7.66% (standard deviation [SD], 0.42%; C) to 14.27% (SD, 0.31%; H), this new genome supports the HBV-I classification as a unique genotype.

Keywords: hepatitis B virus; recombinant virus; recombination; virus classification.

MeSH terms

  • China
  • DNA, Viral / genetics
  • Genotype*
  • Hepatitis B / virology*
  • Hepatitis B Surface Antigens / genetics
  • Hepatitis B virus / classification*
  • Hepatitis B virus / genetics
  • Hepatitis B virus / isolation & purification*
  • Humans
  • Sequence Analysis, DNA
  • Sequence Deletion
  • Thailand


  • DNA, Viral
  • Hepatitis B Surface Antigens