2006年-2008年河南省PRRSV分子流行病学调查

MOLECULAR EPIDEMIOLOGY OF PORCINE REPRODUCTIVE AND RESPIRATORY SYNDROME VIRUS IN HENAN PROVINCE FROM 2006-2008

根据GenBank公布的猪繁殖与呼吸综合征病毒(PRRSV)ATCC VR-2332株的NSP2,ORF5-7基因的核苷酸序列,设计合成5对特异性引物,用RT-PCR方法扩增出10株PRRSV河南地方株的NSP2和ORF5-7片段,将扩增片段克隆到pMD-18T载体并进行测序。应用DNAStar序列分析软件对分离株的NSP2和ORF5-7基因和其推导的氨基酸序列与不同来源的PRRS毒株进行了同源性比较,结果表明PRRSV河南分离株的NSP2和ORF5-7基因与不同来源美洲型毒株之间的同源性分别为89.1%-98.1%和81.4%-96.1%,而与欧洲型毒株之间的同源性仅为46.7%-61.7%和44.7%-45.9%;同时将PRRSV河南分离株NSP2和ORF5-7基因的推导氨基酸序列与其他美洲型PRRSV毒株进行变异分析比较,证实了PRRSV河南分离株NSP2和ORF5-7基因发生了变异。

Five pairs of specific primer of Nsp2 and ORF5 -7 genes were designed according to the gene sequence of ATCC VR - 2322 of American standard strain. The cDNA fragment of PRRSV Henan strains were amplied by RT - PCR, then cloned into pMD - 18T vector respectively and sequenced. After sequencing, the Nsp2 and ORF5 -7 genes were blasted with PRRSV genome sequence downloaded from NCBI. Compared with other American isolated, the homology rate of the Nsp2 and ORF5 -7 genes and amino acid were 89.1% to 98.1% and 81.4% to 97.1% respectively. Compared with other Europe isolated, the homology rate of the Nsp2 and ORF5 - 7 genes and amino acid were 46.9% to 61.2% and 41.4% to 45.1% respectively. The result showed that the PRRSV isola- ted from Henan were mutant compare with American genetype.