Molecular Biology
Although it was originally classified in the Caliciviridae family, the virus has since been classified into the genus Hepevirus, but was not assigned to a viral family. The virus itself is a small non-enveloped particle.
The genome is approximately 7200 bases in length, is a polyadenylated single-strand RNA molecule that contains three discontinuous and partially overlapping open reading frames (ORFs) along with 5' and 3' cis-acting elements, which have important roles in HEV replication and transcription. ORF1 encode a methyltransferase, protease, helicase and replicase; ORF2 encode the capsid protein and ORF3 encodes a protein of undefined function. A three-dimensional, atomic-resolution structure of the capsid protein in the context of a virus-like particle has been described. An in vitro culture system is not yet available.
As of 2009 there are approximately 1,600 sequences of both human and animal isolates of HEV available in open-access sequence databases.
Species of this genus infect humans, pigs, boars, deer, rats, rabbits and birds.
Read more about this topic: Hepatitis E
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