我国部分地区禽流感病毒流行株的分子流行病学调查

Molecular Epidemiology of AIV epidemic strains form parts of China

为了解近年来禽流感病毒在我国部分地区家禽中的流行情况，深入阐明我国禽流感病毒流行株的HA和NP基因的进化关系及遗传进化过程，本研究采用RT-PCR方法，对我国广西、河北、湖南、河南、山东等地采集的病料进行检测，并对其中19株H5N1阳性分离株进行HA和NP基因测序，将测定的序列与参照序列对比，运用DNAStar软件对核苷酸序列进行同源性和遗传进化分析。结果表明，分离的禽流感流行株因地域的不同、时间的差异、宿主的不同，禽流感病毒HA基因核苷酸序列的同源性在96．0％～99．7％之间，推导的氨基酸序列的同源性在95．8％～99．6％之间；禽流感病毒NP基因核苷酸序列的同源性在68．2％～99．7％之间，推导的氨基酸序列的同源性在65．5％～99．8％之间。各分离株在遗传进化树上并不集中处于一个分枝中，而是处于遗传进化树的不同位置，说明我国禽流感病毒可能已经发生部分变异，这些禽流感病毒起源于不同的种系，但可能具有共同的祖先。

To determine the epidemiology of avian influenza virus in poultry in recent years in parts of our country and further clarify the evolutionary relationships in HA and NP genes of the avian influenza vi- rus epidemic strains, pathological materials were collected from Guangxi, Hebei, Hunan, Henan, Shan- dong and other places and examined using RT-PCR. 19 strains of HSN1 positive isolates were sequenced, and the sequencing results were compared with the reference virus sequence. Homology and genetic evolu- tion analysis were performed on the nucleotide sequence using DNAStar software. Results show that AIV HSN1 isolates from different locations, time and host, homology of HA gene is between 96. 0% and 99.7%. Homology of the amino acid sequence is between 95.8% and 99.6%. Homology of NP gene is be- tween 68.2% and 99.7%, Homology of the amino acid sequence is between 65.5% and 99.8%%. These data show that the isolates in genetic evolutionary tree may have a common ancestor.