| The variant characteristics of the porcine reproductive and respiratory syndrome virus (PRRSV) isolated from Xinjiang were studied. Identification of the PRRSV strain isolated from lungs in the clinical diseased piglets was performed
by RT-PCR and sequence analysis of Nsp2 gene and ORF5 gene. The sequence analysis showed that the Xinjiang isolate
belonged to the American strain of PRRSV, named XJ-Q. It was very closer to Hongkong HK13 and homology of XJ-Q was
93.6%-99.8%, next to HUB1 and JXA1 isolates in China with 92.4% homology. However, the Nsp2 protein of XJ-Q had a
total of 30 amino acids deletion between aa532 and aa560, compared with that of North American standard strain VR-2332
in Gene Bank, and also had another unique 3 amino acids deletion between aa487 and aa489 within its Nsp2-coding region,
compared with those of other variant PRRSV strains isolated from China in recent years. The analysis showed that XJ-Q
isolate represents a newly emerged PRRSV variant, belonging to the American strain of PRRSV. |
