Phylogenetic analysis of Toggenburg orbivirus (TOV) (shaded regions) genome segments by ClustalW alignment (16) and subsequent neighbor-joining tree construction by MEGA version 4 software (15). GenBank accession numbers are indicated for all orbivirus sequences used to construct dendrograms. A) Segment 5; B) segment 6; C) segment 7; D) segment 8; E) segment 9; F) segment 10. BTV, bluetongue virus; EHDV, epizootic hemorrhagic disease virus. Segments show only relevant parts of dendrograms. **Segment 10 sequence of BTV-8 currently circulating in northern Europe. Scale bars indicate number of nucleotide substitutions per site.