2011年猪流行性腹泻病毒的遗传变异分析

Genetic variation analysis of porcine epidemic diarrhea virus isolated in 2011

为分析猪流行性腹泻病毒(PEDV)的遗传变异情况,本研究设计合成2对扩增S1基因的引物,利用套式RT-PCR方法,对2011年分离的17个PEDV S1基因进行扩增、克隆和序列测定;并将其进行比对和遗传演化分析。结果表明:17个PEDV S1基因序列与参考病毒株S1基因核苷酸序列同源性为90.54%～99.96%,与经典病毒株CV777相比,其中有6个S1基因在453 bp～454 bp处存在3个核苷酸的缺失;一个在453 bp～454 bp处缺失6个核苷酸;其它10个S1基因在173 bp～186 bp之间存在12个核苷酸的插入,413 bp～417 bp之间有3个核苷酸的插入,467 bp～468 bp处缺失6个核苷酸,插入和缺失位点与韩国病毒株KNU-0901、KNU-0905、KNU-0801相似。S1基因系统进化树分析表明,PEDV S1基因分为3群,其中7个S1基因属于PEDVⅠ群,另外10个属于PEDVⅢ群。

Porcine epidemic diarrhea virus （PEDV） causes an acute and highly contagious enteric disease in swine. To investigate the variation in S1 gene of PEDV, a total of 17 PEDV S1 genes were cloned and sequenced from different swine breeding farms in different provinces in 2011. Compared with CV777, there were 3 nucleotides deletion between 453 bp to 454 bp in 6 isolates; There were 6 nucleotide deletion between 453 bp to 454 bp in one isolate. There were 12 nucleotide insertions between173 bp to 186 bp, 3 nucleotide insertions between 413 bp to 417 bp and 6 nucleotide deletion between 467 bp to 468 bp, respectively, in the other 10 isolates. The nucleotide insertion and deletion were similar to KNU-0901, KNU-0905, KNU-0801 strain isolated in Korea. Sequence analysis showed that SI gene shared 90.54% to 99.96% nucleotide identities with PEDV reference sequences. Phylogenetic analysis revealed that 7 of PEDV S1 gene belong to the first group. Other 10 of PEDV S1 gene belong to the third grouD.