title: Sequence variation and evolution of Cryphonectria hypovirus 1 (CHV-1) in Europe.
abstract: Cryphonectria hypovirus 1 (CHV-1) acts as a naturally occurring biological control agent for chestnut blight, a destructive fungal disease of chestnut trees, which has been introduced into Europe in the 1930s. We have determined partial nucleotide and deduced amino acid sequences of the ORF A of 47 CHV-1 isolates collected in Europe over a period of 28 years. Phylogenetic analysis revealed the presence of four groups or single viruses, which showed sequence divergences ranging from 11 to 19%. These results confirm the previous subtype classification based on RFLP markers, with the exception of the two CHV-1 subtypes E and D, which appear to be related closer than anticipated previously. Dates of divergences between CHV-1 subtypes, calculated from nucleotide substitution rates, indicate that the CHV-1 subtypes diverged several hundreds years ago. Our results suggest that the genetic variation among CHV-1 subtypes did not evolve in Europe and support the hypothesis of multiple introductions of CHV-1 into Europe.
authors.affiliation: WSL Swiss Federal Institute for Forest, Snow and Landscape Research, CH-8903, Birmensdorf, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Gobbin
authors.forename: P J
authors.initials: PJ
authors.lastname: Hoegger
authors.forename: U
authors.initials: U
authors.lastname: Heiniger
authors.forename: D
authors.initials: D
authors.lastname: Rigling
mesh_terms: D001203:Ascomycota / Q000821:virology*; D005060:Europe; D019143:Evolution, Molecular; D005814:Genes, Viral; D014644:Genetic Variation; D008969:Molecular Sequence Data; D010802:Phylogeny; D017354:Point Mutation / Q000235:genetics; D012328:RNA Viruses / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D012367:RNA, Viral / Q000302:isolation & purification; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D012689:Sequence Homology, Nucleic Acid
chemical_list: D012367:RNA, Viral