Update: proposed reference sequences for subtypes of hepatitis E virus (species Orthohepevirus A)

Abstract

In this recommendation, we update our 2016 table of reference sequences of subtypes of hepatitis E virus (HEV; species Orthohepevirus A, family Hepeviridae) for which complete genome sequences are available (Smith et al., 2016). This takes into account subsequent publications describing novel viruses and additional proposals for subtype names; there are now eight genotypes and 36 subtypes. Although it remains difficult to define strict criteria for distinguishing between virus subtypes, and is not within the remit of the International Committee on Taxonomy of Viruses (ICTV), the use of agreed reference sequences will bring clarity and stability to researchers, epidemiologists and clinicians working with HEV.

Keywords: Hepeviridae; Orthohepevirus A; hepatitis E virus.

Fig. 1.

Phylogenetic analysis of HEV complete coding region sequences of (a) genotype 1 (n=77), (b) genotype 3 (n=384), (c) subtype 3ra (n=22), (d) genotype 4 (n=112) and (e) genotypes 5–8 and reference sequences of genotypes 1–4. Neighbour-joining trees of Jukes–Cantor distances was produced using mega7 [10]. Numbers indicate nodes where bootstrap support was >70 % out of 1000 replicates. Tips are collapsed for subtypes (panels a, b and d) or genotypes (panel e) for which multiple sequences are available. Bar: nucleotide sequence distances.