山西省部分地区猪圆环病毒2型基因遗传变异分析

Genetic Variation Analysis of Porcine Circovirus Type 2 Gene in Some Areas of Shanxi Province

为了解山西省猪圆环病毒2型(PCV2)基因的遗传变异情况,用特异性引物对山西省部分地区PCV2疑似病猪的病料进行了PCV2基因扩增,利用DNAStar和MEGA-X对PCV2全基因和ORF2基因进行遗传变异分析,并对ORF2基因推导的Cap蛋白进行变异分析。结果表明,获得6株完整的PCV2基因序列,基因全长1767 bp左右;6株PCV2全基因和ORF2基因之间核苷酸同源性分别为96.6%~99.9%和94.8%~99.9%,与GenBank上已发布的国内外参考毒株全基因间和ORF2基因间同源性分别为94.6%~99.8%和91.5%~99.9%。6株PCV2毒株ORF2基因推导的Cap蛋白氨基酸之间同源性为94.0%~100%,与GenBank上已发布的国内外参考毒株同源性为88.0%~100%。在鉴定测序的6株PCV2中,1株属于PCV 2d型,5株属于PCV 2b型,推断目前山西省PCV2流行毒株以PCV 2b型为主。

To understand the genetic variation of porcine circovirus type 2(PCV2)in Shanxi province,the PCV2 genes of suspected pigs from some areas of Shanxi province were amplified by PCR with specific primers,and the complete genomes and ORF2 genes of the PCV2 viruses were analyzed by DNAStar and MEGA-X,and the variation of Cap protein derived from ORF2 gene of PCV2 was analyzed.The result showed that six complete PCV2 gene sequences were obtained,and a total length genome was 1767 bp or 1768 bp.The nucleotide homology of the complete genome and ORF2 genes among the six PCV2 strains was 96.6%-99.9%and 94.8%-99.9%,respectively.The homology of the full-length genomes and ORF2 genes between the the six PCV2 viruses and the published domestic and foreign reference strains on GenBank were 94.6%-99.8%and 91.5%-99.9%,respectively.The amino acid homology of the Cap protein deduced from ORF2 gene of the six PCV2 strains was 94.0%-100%and 88.0%-100%with the reference strains published in GenBank.Among the six PCV2 strains identified and sequenced in our study,one strain was PCV 2d type and five strains were PCV 2b type,which indicated that PCV 2b was the main prevalent subtype in Shanxi province.