Table_1_Classification of the Zoonotic Hepatitis E Virus Genotype 3 Into Distinct Subgenotypes.DOCX

Hepatitis E virus (HEV) genotype 3 is the most common genotype linked to HEV infections in Europe and America. Three major clades (HEV-3.1, HEV-3.2, and HEV-3.3) have been identified but the overlaps between intra-subtype and inter-subtype p-distances make subtype classification inconsistent. Reference sequences have been proposed to facilitate communication between researchers and new putative subtypes have been identified recently. We have used the full or near full-length HEV-3 genome sequences available in the Genbank database (April 2020; n = 503) and distance analyses of clades HEV-3.1 and HEV-3.2 to determine a p-distance cut-off (0.093 nt substitutions/site) in order to define subtypes. This could help to harmonize HEV-3 genotyping, facilitate molecular epidemiology studies and investigations of the biological and clinical differences between HEV-3 subtypes.

戊型肝炎病毒（Hepatitis E virus, HEV）3型是欧美地区与HEV感染相关的最常见基因型。目前已鉴定出3个主要进化枝（clade）：HEV-3.1、HEV-3.2与HEV-3.3，但亚型内与亚型间的p距离（p-distance）存在重叠，导致亚型分类标准不统一。学界已提出参考序列以促进研究者间的学术交流，且近期又鉴定出若干新的疑似亚型。本研究使用了GenBank数据库中截至2020年4月的全部或近全长HEV-3基因组序列（共503条，n=503），并针对HEV-3.1与HEV-3.2两个进化枝开展距离分析，确定了用于界定亚型的p距离阈值（0.093次核苷酸替换每位点）。该阈值有助于统一HEV-3基因分型工作，推动分子流行病学研究，以及探究HEV-3各亚型间的生物学与临床差异。