Fig. 4.

The phylogenetic tree of 107 selected PRV S1 segment sequences was constructed using Maximum Likelihood analysis using PhyML [55]. An outgroup (GenBank accession number: AF059720) was used to determine its root, but the outgroup itself was not included in the tree. The bootstrapping procedure was applied for 1000 times and the branches with 70% or higher bootstrapping support values were marked: each bootstrapping value corresponds to the branch on the same vertical level. The classification of PRV into two genotypes (I and II) and four sub-genotypes (Ia, Ib, IIa, and IIb) is also shown. The PRV S1 segment sequences obtained in this study from the samples of escaped farmed Atlantic salmon and the market-bought fish labeled “Product of Iceland” are highlighted in yellow