Lee Chang-Hee, Byun Sung-Hwan, Lee Youn-Jeong, Mo In-Pil
Avian Disease Laboratory, College of Veterinary Medicine, Chungbuk National University, Cheongju 361-763, Korea.
Virus Genes. 2012 Aug;45(1):38-47. doi: 10.1007/s11262-012-0737-6. Epub 2012 Mar 28.
We performed whole genome sequencing of 22 H9N2 avian influenza viruses (AIV) isolated from domestic laying hens on farms between 2005 and 2008, and compared the sequences with viruses previously reported in Asia. A previous study revealed that two antigenically distinct sublineages were established within the MS96 lineage by antigenic drift since the first H9N2 AIV outbreak in South Korea. We designated them as the 01310-like lineage and the 116/04-like lineage. Since late 2004, most identified isolates in Korea have belonged to the 116/04-like lineage, however, in this study we found that six among twenty-two isolates were belonged to 01310-like lineage, indicating that the genetic divergence is still occurring after 2004. Furthermore, it is noteworthy that five isolates among the defined 01310-like lineage had a 24 amino acid deletion in the neuraminidase stalk region, which were not in any other H9N2 isolates previously reported. The internal genes analysis demonstrated extensive reassortment events among isolates from poultry farms, live bird markets, and wild birds, and multiple new genotypes were identified. We identified several features of gene evolution in H9N2 AIV suggesting that the long-term H9N2 AIV surveillance study should be continued in South Korea.
我们对2005年至2008年间从国内蛋鸡养殖场分离出的22株H9N2禽流感病毒（AIV）进行了全基因组测序，并将这些序列与亚洲此前报道的病毒进行了比较。此前的一项研究表明，自韩国首次爆发H9N2 AIV以来，通过抗原漂移在MS96谱系中形成了两个抗原性不同的亚谱系。我们将它们指定为01310样谱系和116/04样谱系。自2004年末以来，韩国大多数鉴定出的分离株都属于116/04样谱系，然而，在本研究中我们发现22株分离株中有6株属于01310样谱系，这表明2004年之后遗传分化仍在发生。此外，值得注意的是，在确定的01310样谱系中有5株分离株在神经氨酸酶茎区有24个氨基酸的缺失，这在之前报道的任何其他H9N2分离株中都没有。内部基因分析表明，来自家禽养殖场、活禽市场和野生鸟类的分离株之间发生了广泛的重配事件，并鉴定出了多个新的基因型。我们确定了H9N2 AIV基因进化的几个特征，这表明韩国应继续进行长期的H9N2 AIV监测研究。
