Infectious hematopoietic necrosis virus: monophyletic origin of European isolates from North American Genogroup M

Genotyping of Korean isolates of infectious hematopoietic necrosis virus (IHNV) based on the glycoprotein gene

“…The genogroups U, M and L respectively correlated to virus isolates from the upper, middle and lower portions of the geographic range of IHNV in North America. A fourth cluster was for European isolates from Germany, Italy and France [1]. As previously reported, Japanese isolates from 1971 to 1982 were included in the U genogroup cluster, while Japanese isolates from 1980 to 1996 comprised a fifth cluster designated genogroup JRt [11].…”

“…More recently, two additional genogroups for European and Japanese isolates were identified [1,11]. It is interesting that the genogroup for European isolates shared a common source with the American genogroup M [1], while the genogroup for Japanese isolates was closely related with the American genogroup U [11]. Thus, at present, a total of five genogroups correlating with the geographic areas have been identified among worldwide isolates of IHNV.…”

“…The genogroup U includes isolates from Alaska, British Columbia, Washington coastal watersheds and the Columbia River basin; the genogroup M includes isolates from the Columbia River basin and Idaho; and the genogroup L includes isolates from California and the southern Oregon coast. More recently, two additional genogroups for European and Japanese isolates were identified [1,11]. It is interesting that the genogroup for European isolates shared a common source with the American genogroup M [1], while the genogroup for Japanese isolates was closely related with the American genogroup U [11].…”

“…The determined G gene ORFs without the PCR primer sequences showed more than 95% identity to each other, and more than 93% identity with those sequences of 38 worldwide IHNV isolates (Table 1). A radial tree of phylogeny based on the determined G gene nucleotide sequences revealed the five major clusters described in previous studies [1,7,11] (Fig. 2).…”

“…The IHNV genome is a non-segmented and single-stranded negative-sense RNA with approximately 11,000 nucleotides containing six genes in the order 3'-N-P-M-G-NV-L-5' encoding the nucleocapsid protein (N), phosphoprotein (P), matrix protein (M), glycoprotein (G), non-virion protein (NV) and polymerase (L) genes, respectively [6,9]. The G, N and NV genes have been used for analyses of IHNV evolution, diversity and phylogenetic relationship among the worldwide isolates [1,3,7,10,11,16,17].…”