Prelude to a panzootic: gene flow and immunogenetic variation in northern little brown myotis vulnerable to bat white-nose syndrome

The fungus that causes bat white-nose syndrome (WNS) recently leaped from eastern North America to the Pacific Coast. The pathogen’s spread is associated with the genetic population structure of a host (Myotis lucifugus). To understand the fine-scale neutral and immunogenetic variation among northern populations of M. lucifugus, we sampled 1142 individuals across the species’ northern range. We used genotypes at 11 microsatellite loci to reveal the genetic structure of, and directional gene flow among, populations to predict the likely future spread of the pathogen in the northwest and to estimate effective population size (Ne). We also pyrosequenced the DRB1-like exon 2 of the class II major histocompatibility complex (MHC) in 160 individuals to explore immunogenetic selection by WNS. We identified three major neutral genetic clusters: Eastern, Montane Cordillera (and adjacent sampling areas), and Haida Gwaii, with admixture at intermediate areas and significant substructure west of th...引发蝙蝠白鼻综合征（WNS）的真菌近期从北美东部跳跃式扩散至太平洋沿岸。该病原体的扩散与宿主（Myotis lucifugus）的种群遗传结构紧密相关。为解析M. lucifugus北部种群的精细尺度中性遗传与免疫遗传变异，我们在该物种的北部分布范围内采集了1142份个体样本。我们利用11个微卫星位点的基因型，解析了种群的遗传结构及种群间的定向基因流，以此预测该病原体在西北部的潜在未来扩散趋势，并估算有效种群大小（Ne）。我们还对160份个体的主要组织相容性复合体II类（MHC）DRB1样外显子2进行了焦磷酸测序，以探究WNS介导的免疫遗传选择。我们共识别出三大中性遗传类群：东部类群、山地科迪勒拉（及周边采样区域）类群与海达瓜依类群，中间区域存在遗传混合，且西部存在显著的亚结构……