牛病毒性腹泻病毒基因组快速进化表现出来的遗传多样性

The Genetic Diversity Represented by Genome with Rapid Evolutionary Rate of Bovine Viral Diarrhea Virus

牛病毒性腹泻病毒(Bovine viral diarrhea virus, BVDV)基因组的高突变性和同源/异源重组性导致其成为一种较难防控的家畜病原体。目前普遍接受的两种基因型是BVDV-1和BVDV-2,其中基因1型含有21个亚型而基因2型含有4个亚型。在流行态势上,BVDV-1无论在遗传多样性还是分离毒株的数量上均高于BVDV-2。虽然BVDV-1和BVDV-2在基因组遗传特征上存在明显的遗传差异,但是其基因组内部特定区域在遗传进化上存在着密切关联。除了病毒基因组自身高变异的特性外,同源/异源RNA重组在BVDV遗传变异进程中也发挥着重要的作用。借助这些遗传进化的途径,BVDV在世界各地的流行传播可以用“随心所欲”来形容。BVDV的流行特征总体表现为基因1型的毒株为主要流行毒株,各基因亚型之间交替更迭并呈现遗传多样性。鉴于BVDV遗传进化的多变性和复杂性,紧密追踪主要流行基因亚型的更迭以及收集不同基因亚型的特征性遗传信息对于制定切实有效的BVDV防控措施具有实际意义。

Bovine viral diarrhea virus(BVDV), which, has a genome with high mutation rate and homologous/heterologous RNA recombination, is an important pathogen of livestock. Two main types have been identified: BVDV-1(21 subtypes) and BVDV-2(4 subtypes). Generally, viral population of BVDV-1 has a broader distribution than BVDV-2. Although the genetic feature of BVDV-1 differs from those of BVDV-2 on nucleotide level, specific regions in the viral genome share conserved evolutionary information. Apart from high evolutionary rate, homologous/heterologous RNA recombination play important roles in genetic diversity of BVDV. Depending on these evolutionary mechanisms, BVDV transmission in animals is rapidly and widespread, with various changes between viral subtypes. The main epidemic strain is BVDV-1 and the gene subtypes show genetic diversity. Based on the complex genetic diversity of BVDV, it is important to pay attention to changing BVDV subtypes and collect evolutionary information about BVDV subtypes for preventing and controlling BVDV epidemic efficiently.