Verification of bluetongue virus S9 segment nucleotide sequences

During the course of our bluetongue virus (BTV) nucleic acid sequence inves tigations, conflicts among United States (US) prototype BTV S9 genome segme nt sequences deposited in GenBank were noted. In order to rectify these int er-laboratory discrepancies, the S9 segments of Arthropod-borne Animal Dise ases Research Laboratory (ABADRL)-stored US prototype BTV 2, BTV 10, BTV 11 , BTV 13, and BTV 17 isolates were resequenced. Our S9 sequences, determine d by direct sequencing of full-length reverse transcriptase-polymerase chai n reaction (RT-PCR) generated amplicons, shared 99% or greater nucleotide i dentity with one or more respective S9 sequences previously reported. Possi ble sources of remaining unsupported US prototype BTV S9 sequences were eva luated by amplifying and sequencing the S9 segments of BTV 2 Ona A strain, South African (SA) prototype BTV 1, BTV 2, and BTV 4 strains, and the North American (NA) prototype epizootic hemorrhagic disease virus (EHDV) serotyp e 2 (Alberta) strain. Comparative analysis using these S9 sequences, as wel l as sequences of US BTV 2 field isolates, identified potential contributor s to inter-laboratory sequence disagreements. (C) 2001 Elsevier Science B.V . All rights reserved.