[ Objective] The study aimed to investigate the genetic variation characters of entire sequences between two H9N2 subtype avian influenza virus strains and other reference strains. [ Method] The entire sequences of 8 genes were obtained by using RT-PCR, and these sequences were analyzed with that of six H9N2 subtype avian influenza isolates in homology comparison and genetic evolution relation. [ Result] The results showed that the nucleotide sequence of entire gene of the strain shared 91.1％ - 95.4％ homology with other seven reference strains, and PG08 shared the highest homology 91.3％ with C/BJ/1/94; ZD06 shared the highest homology 92.3％ with D/HK/Y280/97. HA cleavage sites of two H9N2 subtype avian influenza virus isolated strains were PARSSR/GLF, typical of mildly pathogenic avian influenza virus. [ Conclusion ] Phylogenetic tree for entire gene of eight strains showed that the genetic relationship was the closest between ZD06 and C/Pak/2/99 strains, which belonged to the Eurasian lineage; PG08 shared the highest homology 91.3％ with ZD06, it may be the product of gene rearrangements of other sub-lines.%[目的]探讨2株H9N2分离毒株与其他参考毒株的全基因组遗传变异关系.[方法]采用RT-PCR技术扩增了2株H9N2亚型禽流感病毒分离株8个基因片段的全基因序列,并对所得序列与6个参考毒株进行了同源性比较及遗传进化树分析.[结果]2个毒株与6个参考毒株全基因组同源性在91.1%～95.4%,PG08与C/BJ/1/94的全基因序列的核苷酸同源性最高为91.3%;而ZD06与D/HK/Y280/97最高为92.3%.2个分离株的HA基因裂解位点均为PARSSR/GLF,均为H9N2低致病力禽流感病毒.[结论]ZD06株与C/Pak/2/99的亲缘关系最近,属欧亚种系;PG08株与其他毒株亲缘关系稍远,它可能是不同亚支基因重排的产物.
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