title: Whole-genome analysis of piscine reovirus (PRV) shows PRV represents a new genus in family Reoviridae and its genome segment S1 sequences group it into two separate sub-genotypes.
abstract: BACKGROUND
  Piscine reovirus (PRV) is a newly discovered fish reovirus of anadromous and marine fish ubiquitous among fish in Norwegian salmon farms, and likely the causative agent of heart and skeletal muscle inflammation (HSMI). HSMI is an increasingly economically significant disease in Atlantic salmon (Salmo salar) farms. The nucleotide sequence data available for PRV are limited, and there is no genetic information on this virus outside of Norway and none from wild fish.
  
  
  METHODS
  RT-PCR amplification and sequencing were used to obtain the complete viral genome of PRV (10 segments) from western Canada and Chile. The genetic diversity among the PRV strains and their relationship to Norwegian PRV isolates were determined by phylogenetic analyses and sequence identity comparisons.
  
  
  RESULTS
  PRV is distantly related to members of the genera Orthoreovirus and Aquareovirus and an unambiguous new genus within the family Reoviridae. The Canadian and Norwegian PRV strains are most divergent in the segment S1 and S4 encoded proteins. Phylogenetic analysis of PRV S1 sequences, for which the largest number of complete sequences from different "isolates" is available, grouped Norwegian PRV strains into a single genotype, Genotype I, with sub-genotypes, Ia and Ib. The Canadian PRV strains matched sub-genotype Ia and Chilean PRV strains matched sub-genotype Ib.
  
  
  CONCLUSIONS
  PRV should be considered as a member of a new genus within the family Reoviridae with two major Norwegian sub-genotypes. The Canadian PRV diverged from Norwegian sub-genotype Ia around 2007 ± 1, whereas the Chilean PRV diverged from Norwegian sub-genotype Ib around 2008 ± 1.
authors.affiliation: Department of Pathology and Microbiology, Atlantic Veterinary College, University of Prince Edward Island, 550 University Ave, Charlottetown, PEI C1A 4P3, Canada. kibenge@upei.ca
authors.forename: Molly J T
authors.initials: MJ
authors.lastname: Kibenge
authors.forename: Tokinori
authors.initials: T
authors.lastname: Iwamoto
authors.forename: Yingwei
authors.initials: Y
authors.lastname: Wang
authors.forename: Alexandra
authors.initials: A
authors.lastname: Morton
authors.forename: Marcos G
authors.initials: MG
authors.lastname: Godoy
authors.forename: Frederick S B
authors.initials: FS
authors.lastname: Kibenge
mesh_terms: D000818:Animals; D002170:Canada; D002677:Chile; D016000:Cluster Analysis; D014644:Genetic Variation; D016679:Genome, Viral; D005838:Genotype; D008969:Molecular Sequence Data; D009664:Norway; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics*; D012087:Reoviridae / Q000235:genetics* / Q000302:isolation & purification; D020317:Salmo salar / Q000821:virology*; D017422:Sequence Analysis, DNA
chemical_list: D012367:RNA, Viral