Molecular evolution and phylogeography of infectious hematopoietic necrosis virus with a focus on its presence in France over the last 30 years
|Author(s)||Bellec Laure1, 2, Louboutin Lenaig3, Cabon Joelle3, Castric Jeanne3, Cozien Joelle4, Thiery Richard5, Morin Thierry3|
|Affiliation(s)||1 : IFREMER, Ctr Brest, REM EEP LEP, CS10070, F-29280 Plouzane, France.
2 : IFREMER, Ctr Brest, REM EEP LMEE, UMR6197,CS10070, F-29280 Plouzane, France.
3 : Bretagne Loire Univ, French Agcy Food Environm & Occupat Hlth & Safety, Natl Reference Lab Regulated Fish Dis, Viral Fish Pathol Unit,Ploufragan Plouzane Lab, Technopole Brest Iroise,BP 70, Plouzane, France.
4 : IFREMER, Lab Sante Environm & Microbiol PDG RBE SG2M LSEM, Technopole Brest Iroise,BP 70, F-29280 Plouzane, France.
5 : French Agcy Food Environm & Occupat Hlth & Safety, Sophia Antipolis Lab, F-06902 Sophia Antipolis, France.
|Source||Journal Of General Virology (0022-1317) (Microbiology Soc), 2017-10 , Vol. 98 , N. 10 , P. 2438-2446|
|WOS© Times Cited||8|
|Keyword(s)||infectious hematopoietic necrosis virus, evolutionary dynamics, dates of divergence, phylogeography, molecular epidemiology|
Infectious hematopoietic necrosis virus (IHNV) is among the most important pathogens affecting the salmonid industry. Here, we investigated the molecular evolution and circulation of isolates from 11 countries or regions all over the world, with a special focus on the epidemiological situation in France. The phylogeography, time to the most recent common ancestor (TMRCA) and nucleotide substitution rate were studied using 118 full-length glycoprotein gene sequences isolated from 9 countries (5 genogroups) over a period of 47 years. The TMRCA dates back to 1943, with the L genogroup identified as the likely root (67 %), which is consistent with the first report of this pathogen in the USA. A Bayesian inference approach was applied to the partial glycoprotein gene sequences of 88 representative strains isolated in France over the period 1987–2015. The genetic diversity of these 88 sequences showed mean nucleotide and amino-acid identities of 97.1 and 97.8 %, respectively, and a d N/d S ratio (non-synonymous to synonymous mutations) of 0.25, indicating purifying selection. The French viral populations are divided into eight sub-clades and four individual isolates, with a clear spatial differentiation, suggesting the predominant role of local reservoirs in contamination. The atypical ‘signatures’ of some isolates underlined the usefulness of molecular phylogeny for epidemiological investigations that track the spread of IHNV.