First report of a variant bovine papillomavirus type 2 (BPV-2) in cattle in the Iberian Peninsula.

Infections caused by bovine papillomavirus (BPV) have been described worldwide. Some types, like BPV-1 and BPV-2, have been reported in association with skin warts and fibropapillomas in cattle and sarcoids in equids. In this study we have investigated the presence of BPV in cutaneous warts isolated from a steer in Spain. Cutaneous fibropapillomatosis was confirmed by histopathological analysis. Complete genome was amplified by multiple-primed rolling circle and the L1, E5 and E6 genes were sequenced. The isolate was classified as a variant of BPV-2 on the basis of the L1 gene sequences. Genetic variability of L1, E5 and E6 genes was compared with BPV-2 isolates from different hosts in several continents. Some mutations involved non-synonymous substitutions when compared to the prototype strain. One of these non-conservative mutations was located in the jelly roll β-barrel of the EF loop of the capsid protein (encoded by L1). This study presents the first report of a variant of BPV-2 infection in the Iberian Peninsula and contributes to extend the knowledge of the spreading and circulation of BPV.