陕西省部分地区猪圆环病毒2型全基因组的遗传变异分析

Genetic Variation Analysis of Complete Genome of Porcine Circovirus Type 2 in Partial Regions of Shaanxi Province

为了解陕西省猪圆环病毒2型(PCV2)的遗传变异情况,根据GenBank登录的PCV2全基因组序列,设计1对引物,从陕西省部分地区规模化猪场疑似PCV2感染的病猪采集病料9份,应用PCR扩增PCV2的全基因,其中6份为阳性,并对扩增的6个PCV2全基因组序列进行测序和序列分析。基因测序表明,PCV2基因组全长为1 767bp;对6株病毒序列进行同源性比较,6个毒株全基因之间核苷酸同源性为98.3%~100%,与GenBank上已发表的国内外毒株全基因组比较,同源性为96.3%~97.8%;与近几年陕西株比较发现基因变异程度不稳定,与2013年分离株(KX352154.1)同源性最高,2015年分离株(KX352159.1)次之,反而与2014年分离株(KX068219.1)最低;对6个毒株的ORF1和ORF2基因进行同源性比较,6个毒株的ORF1和ORF2基因的核苷酸同源性分别为98.1%~100%和98.2%~100%,与GenBank上已发表的国内外参考株ORF1和ORF2基因进行同源性比较,同源性分别为97.6%~99.8%和91.5~96.0%。陕西省流行的PCV2基因组较为保守,变异不大,同源性很高。

In order to understand heredity and variation of porcine circovirus virus type 2in Shaanxi province,according to the published complete genome sequence of PCV2 in GenBank,apair of specific primers were designed and synthesized.The complete genes were amplified with PCR and sequenced from partial regions of Shaanxi province.The six PCV2 complete genome sequences were amplified.The six PCV2 complete genome sequences were 1 767 bp in length.The homology of nucletide sequences of the six strains were 98.3%-100%.Compared with PCV2 complete genome sequences in GenBank,the homology were96.3%-97.8%.Compared with Shaanxi strains,the instability of gene mutation was found.The ORF1 and ORF2of six strains had 98.1%-100% and 98.2%-100% similarities respectively.Compared with PCV2ORF1 and ORF2genome sequences in GenBank,the homology were 97.6%-99.8% and 91.5%-96.0%.Genes of PCV2 in Shaanxi are very conservative and similar.