B. Krossoy et al., Phylogenetic analysis of infectious salmon anaemia virus isolates from Norway, Canada and Scotland, DIS AQU ORG, 44(1), 2001, pp. 1-6
The sequences of gene segments 2 and 8 from 10 different isolates of infect
ious salmon anaemia Virus (ISAV) sampled in Norway, Canada and Scotland bet
ween 1987 and 1999 were determined and compared. Pairwise comparisons revea
led a high degree of homology between the European isolates, with identitie
s of 98 to 100% for both genes examined. The Canadian isolate showed identi
ties of 84 and 87 to 88 % with the European isolates for the nucleotide seq
uence of segments 2 and 8, respectively. Phylogenetic analyses were perform
ed to establish the interrelationship between the European virus isolates.
The evolutionary rate based on 4 Norwegian isolates clustered together in t
he analysis of segment 2 was calculated to be 0.96 x 10(-3) nucleotides sit
e(-1) yr(-1). On the basis of this mutation rate it was estimated that the
Norwegian Glesvaer 90 and Canadian Bay of Fundy 97 isolates diverged around
1900, which coincides with transportation of salmonids between Europe and
North America starting in the late nineteenth century.