title: Phylogenetic analysis of bluetongue virus serotype 4 field isolates from Argentina.
abstract: Bluetongue is an insect-transmitted viral disease of ruminant species, which represents a major barrier to the international trade of animals and their products. Bluetongue virus (BTV) has a genome composed of ten linear segments of dsRNA, which code for at least ten different viral proteins. In South America, serological evidence for the presence of BTV has been found in Peru, Argentina, Brazil, Ecuador and Chile. Brazil and Argentina are the only South American countries where BTV has been isolated. In Brazil, only one BTV isolate, serotype 12, has been reported, whereas in Argentina five BTV serotype 4 isolates have been obtained from cattle without clinical signs. Three of these five isolates were isolated during 1999-2001, whereas two of them were obtained as part of the present work. This study describes sequence comparisons and phylogenetic analyses of segment (Seg)-2, Seg-3, Seg-6, Seg-7 and Seg-10 of the first Argentinian field isolates of BTV. The analysis of Seg-2 and Seg-6 resulted in a single cluster of Argentinian sequences into the serotype 4 clade. In addition, the Argentinian sequences grouped within the nucleotype A clade, along with reference strains. The analysis of Seg-3, Seg-7 and Seg-10 showed that the Argentinian isolates grouped into the western topotype, indicating that the circulating virus had an African/European origin. Phylogenetic analysis revealed that the Argentinian sequences present a South American genetic identity, suggesting an independent lineage evolution.
authors.affiliation: Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina.
authors.forename: D
authors.initials: D
authors.lastname: Legisa
authors.affiliation: Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina.
authors.forename: F
authors.initials: F
authors.lastname: Gonzalez
authors.affiliation: Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina.
authors.forename: G
authors.initials: G
authors.lastname: De Stefano
authors.affiliation: Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina.
authors.forename: A
authors.initials: A
authors.lastname: Pereda
authors.affiliation: Instituto de Virología, CICVyA, INTA-Castelar, Buenos Aires, Argentina.
authors.forename: M J Dus
authors.initials: MJD
authors.lastname: Santos
mesh_terms: D000818:Animals; D001118:Argentina / Q000453:epidemiology; D005075:Biological Evolution; D001819:Bluetongue / Q000453:epidemiology / Q000821:virology*; D001820:Bluetongue virus / Q000145:classification* / Q000235:genetics*; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000821:virology*; D002460:Cell Line; D006224:Cricetinae; D015967:Gene Expression Regulation, Viral; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny