Schmidt Thomas L, Rašić Gordana, Zhang Dongjing, Zheng Xiaoying, Xi Zhiyong, Hoffmann Ary A
School of BioSciences, University of Melbourne, Parkville, VIC, Australia.
Department of Parasitology, Zhongshan School of Medicine, Key Laboratory of Tropical Disease Control, Ministry of Education, Sun Yat-Sen University, Guangzhou, Guangdong, China.
PLoS Negl Trop Dis. 2017 Oct 18;11(10):e0006009. doi: 10.1371/journal.pntd.0006009. eCollection 2017 Oct.
Aedes albopictus is a highly invasive disease vector with an expanding worldwide distribution. Genetic assays using low to medium resolution markers have found little evidence of spatial genetic structure even at broad geographic scales, suggesting frequent passive movement along human transportation networks. Here we analysed genetic structure of Aedes albopictus collected from 12 sample sites in Guangzhou, China, using thousands of genome-wide single nucleotide polymorphisms (SNPs). We found evidence for passive gene flow, with distance from shipping terminals being the strongest predictor of genetic distance among mosquitoes. As further evidence of passive dispersal, we found multiple pairs of full-siblings distributed between two sample sites 3.7 km apart. After accounting for geographical variability, we also found evidence for isolation by distance, previously undetectable in Ae. albopictus. These findings demonstrate how large SNP datasets and spatially-explicit hypothesis testing can be used to decipher processes at finer geographic scales than formerly possible. Our approach can be used to help predict new invasion pathways of Ae. albopictus and to refine strategies for vector control that involve the transformation or suppression of mosquito populations.
白纹伊蚊是一种极具入侵性的疾病媒介，其全球分布范围正在不断扩大。使用低至中等分辨率标记的基因检测发现，即使在广泛的地理尺度上，也几乎没有空间遗传结构的证据，这表明其经常沿着人类交通网络进行被动迁移。在此，我们利用数千个全基因组单核苷酸多态性（SNP）分析了从中国广州12个采样点采集的白纹伊蚊的遗传结构。我们发现了被动基因流动的证据，其中距离航运码头的远近是蚊子之间遗传距离的最强预测因子。作为被动扩散的进一步证据，我们发现多对全同胞分布在相距3.7公里的两个采样点之间。在考虑地理变异性之后，我们还发现了距离隔离的证据，这在以前的白纹伊蚊研究中是无法检测到的。这些发现表明，大型SNP数据集和空间明确的假设检验可用于在比以前更精细的地理尺度上解读相关过程。我们的方法可用于帮助预测白纹伊蚊的新入侵途径，并完善涉及改造或抑制蚊子种群的病媒控制策略。
