[转移贴]JVI：我国科学家发现3个新亚型汉城病毒

cao1976

原贴由503814发表于 2012-2-22 21:13

我国科学家新近研究发现，在浙江、湖南及贵州山区分布有地理聚集特征明显的3个新亚型汉城病毒，并发现目前已知所有汉城病毒至少可分为4个基因亚型，每个亚型间基因组的核苷酸差异在10%以上，具有遗传多样性；中国绝大多数汉城病毒及世界其他所有国家已发现的汉城病毒均为I亚型；褐家鼠的迁徙导致了当今汉城病毒的世界分布。该研究论文日前发表在由美国微生物学会主办的《病毒学杂志》第二期上，并被该杂志作为热点文章推荐。
      领衔该研究的中国疾控中心传染病预防控制所张永振研究员介绍，我国是世界上受肾综合征出血热危害最严重的国家，而该病主要由褐家鼠携带的汉城病毒及黑线姬鼠携带的汉滩病毒引起。既往研究显示，除个别病毒株外，中国及世界上所有其他国家发现的汉城病毒（汉城型汉坦病毒）高度同源，未表现出其他汉坦病毒的遗传多样性及地理聚集特征。中国疾控中心传染病预防控制所与浙江省温州市疾控中心等合作，在我国肾综合征出血热主要流行区开展地理流行病学研究，共采集到4477份褐家鼠等动物标本，从中检测到136份汉坦病毒阳性，进而对其病毒基因序列进行扩增，并与以往研究发现的汉城型汉坦病毒基因序列进行比较及进化分析，获得上述发现。  
      研究人员进一步对我国及世界上已知褐家鼠的线粒体细胞色素b基因序列进行研究发现，这些褐家鼠可以分为两个群，Ⅰ群包括世界上其他国家发现的褐家鼠及分布于我国大部分地区的褐家鼠，该群褐家鼠携带I亚型汉城病毒；Ⅱ群褐家鼠均发现于我国浙江、湖南及贵州的山区。Ⅱ群褐家鼠携带新发现的3个亚型的汉城病毒。由此表明，在山区相对原始的褐家鼠由于长期未受到外来种影响，可能还携带着未知基因亚型汉城病毒。
      张永振称，该研究表明了动物源性疾病与社会生态环境紧密关系，全球化等因素带来的社会生态环境改变，将会导致动物源性疾病的播散。

J. Virol. January 2012 vol. 86 no. 2 972-981
Migration of Norway Rats Resulted in the Worldwide Distribution of Seoul Hantavirus Today

【ABSTRACT】Despite the worldwide distribution, most of the known Seoul viruses (SEOV) are closely related to each other. In this study, the M and the S segment sequences of SEOV were recovered from 130 lung tissue samples (mostly of Norway rats) and from six patient serum samples by reverse transcription-PCR. Genetic analysis revealed that all sequences belong to SEOV and represent 136 novel strains. Phylogenetic analysis of all available M and S segment sequences of SEOV, including 136 novel Chinese strains, revealed four distinct groups. All non-Chinese SEOV strains and most of the Chinese variants fell into the phylogroup A, while the Chinese strains originating from mountainous areas clustered into three other distinct groups (B, C, and D). We estimated that phylogroup A viruses may have arisen only within the last several centuries. All non-Chinese variants appeared to be directly originated from China. Thus, phylogroup A viruses distributed worldwide may share a recent ancestor, whereas SEOV seems to be as diversified genetically as other hantaviruses. In addition, all available mitochondrial DNA (mtDNA) sequences of Norway rats, including our 44 newly recovered mtDNA sequences, were divided into two phylogenetic groups. The first group, which is associated with the group A SEOV variants, included most of rats from China and also all non-Chinese rats, while the second group consisted of a few rats originating only from mountain areas in China. We hypothesize that an ancestor of phylogroup A SEOV variants was first exported from China to Europe and then spread through the New World following the migration of Norway rats.

http://jvi.asm.org/content/86/2/972.abstract