Guangzhou Institute of Advanced Technology, Chinese Academy of Sciences, Nansha, 511458, Guangzhou, China.
BMC Gastroenterol. 2012 Aug 27;12:116. doi: 10.1186/1471-230X-12-116.
Nine subgenotypes from genotype B have been identified for hepatitis B virus (HBV). However, these subgenotypes were less conclusive as they were often designated based on a few representative strains. In addition, subgenotype B6 was designated twice for viruses of different origin.
All complete genome sequences of genotype B HBV were phylogenetically analyzed. Sequence divergences between different potential subgenotypes were also assessed.
Both phylogenetic and sequence divergence analyses supported the designation of subgenotypes B1, B2, B4, and B6 (from Arctic). However, sequence divergences between previously designated B3, B5, B7, B8, B9 and another B6 (from China) were mostly less than 4%. In addition, subgenotype B3 did not form a monophyly.
Current evidence failed to classify original B5, B7, B8, B9, and B6 (from China) as subgenotypes. Instead, they could be considered as a quasi-subgenotype B3 of Southeast Asian and Chinese origin. In addition, previously designated B6 (from Arctic) should be renamed as B5 for continuous numbering. This novel classification is well supported by both the phylogeny and sequence divergence of > 4%.
乙型肝炎病毒（HBV）已鉴定出 9 种 B 基因型的亚基因型。然而，由于这些亚基因型通常是基于少数有代表性的毒株来指定的，因此它们的结论并不明确。此外，亚基因型 B6 曾两次被指定用于来自不同起源的病毒。
对所有 B 基因型 HBV 的完整基因组序列进行系统发育分析。还评估了不同潜在亚基因型之间的序列差异。
系统发育和序列差异分析均支持 B1、B2、B4 和 B6（来自北极）亚基因型的指定。然而，先前指定的 B3、B5、B7、B8、B9 和另一个来自中国的 B6 之间的序列差异大多小于 4%。此外，B3 亚基因型没有形成单系。
目前的证据无法将原始的 B5、B7、B8、B9 和 B6（来自中国）归类为亚基因型。相反，它们可以被视为源自东南亚和中国的准亚基因型 B3。此外，先前指定的来自北极的 B6 应更名为 B5 以进行连续编号。这种新的分类方法得到了系统发育和序列差异分析的支持，其支持率均超过 4%。
