中国白纹伊蚊的种群遗传结构及谱系地理学研究

As one of the important vectors of dengue viruses, Aedes albopictus is widely distributed in China. There is no licensed vaccine or antiviral cures available at present, most efforts to manage the disease are based on vector control. In order to reveal the differential of genetic diversities, genetic structure, gene flow and the extent of divergence among populations, six microsatellite loci and two mitochondrial DNA regions will be used to infer the population genetic structure and phylogeography of Ae. albopictus. And network of haplotypes and phylogenetic trees will be constructed to uncover relationships of different lineages. Then, detail information such as distributions, commerce and transportations will combined with the genetic structure and relationships among populations to interpret formation mechanisms of present distribution patterns, origin and migration routes of different population, which will useful to track and even prevent the movement of target populations. History dynamic and dispersal pattern of populations also be estimated to predict the potential migrations of Ae. albopictus. Results of this study could provide important evidences for the design of effective control strategies of dengue.

白纹伊蚊是传播登革热病毒的重要媒介之一，在我国分布范围广、种群数量大。目前仍没有安全有效的疫苗或抗病毒药物用于登革热的预防，媒介防控成为该病防治的有效途径。本项目拟基于6个微卫星标记和两个线粒体基因，对我国的白纹伊蚊种群开展种群遗传结构和谱系地理学研究。在分子水平上揭示不同地理种群的基因流、遗传多样性差异、遗传结构和分化程度；构建单倍型网络关系图和系统发育树，对地理种群进行亲缘关系分析。基于种群遗传结构和谱系关系的分析结果，结合种群的地理分布以及贸易、交通等信息，探讨不同地理种群现今地理分布格局的形成原因、可能的起源和扩散迁移路线，为追溯或阻断目标种群的扩散提供理论依据；分析种群历史动态和种群扩散格局，预测种群潜在的扩散迁移。本研究的结果将为登革热疾病防控策略的制定提供基础资料。

白纹伊蚊是全球100种最具入侵性的物种之一，目前在世界范围内广泛分布。白纹伊蚊是登革热、黄热病、寨卡等20多种虫媒病毒的传播媒介。媒介生物感染和携带病原体的能力受到种群间遗传差异的影响。本项目基于对不同地理种群广泛采样的基础上探讨了我国白纹伊蚊的种群遗传结构，并结合可获取的国内外数据进一步解析了白纹伊蚊的谱系格局。研究结果表明，我国分布的白纹伊蚊种群处于快速扩张中，除海南种群外，其他地理种群间具有较高的相似性。白纹伊蚊在发生全球扩散之前，在其起源地可能发生过祖先种群的遗传分化，目前在全球范围内快速扩散的仅是其祖先种群的一个分支，其余分支仅在东南亚地区分布。本项目的研究结果可为登革热等虫媒传染病的预警和防控提供参考资料。