2株猪圆环病毒2型分离毒株全基因组的克隆及序列分析

Molecular Cloning,Sequencing and Analysis of the Complete Genome of two Porcine Circovirus Type 2 Isolates

参考GenBank发表的猪圆环病毒2型（PCV2）全基因组序列，设计2对引物，通过PCR技术扩增出2株PCV2流行株的全基因，并进行了序列测定分析．结果表明，2个分离株基因组全长分别为1767bp和1768bp，2个分离株之间的核苷酸相似性为97．3％，与GenBank上已发表的PCV2分离株之间的相似性为93．8％-99．3％．2个分离株的ORF2核苷酸序列相似性分别为91．3％-99．6％和90．6％-98．0％，存在一定的变异．

According to the complete genome sequences of porcine circovirus type 2 （PCV2） published in GenBank,two pairs of primers were designed. The complete genome of two PCV2 isolates were amplified. The resultant PCR products were cloned into pMD18-T vectors, then the nucleotide sequences of the PCV2 complete genome were compared with that of other PCV. The results indicated that the genome of the two isolates were 1 767 bp and 1 768 bp in length, respectively, and nucleofide homology between the two cloned complete genome was 97.3%, nucleofide sequence similarities between the cloned PCV2 complete genome and the published PCV2 complete genome in C, enBank were from 93. 8% to 99. 3%. Nucleotide sequence similarities of ORF2 were from 91.3% to 99. 6% and from 90. 6% to 98.0%, respectively.