A Multifaceted Approach Reveals Complex Genomic Mediation of White-Nose Syndrome Adaptative Response in the Little Brown Bat (Myotis lucifugus).

Novel pathogens have become a major challenge faced by wildlife in the Anthropocene. White-nose syndrome (WNS) has decimated bat populations across North America over the last two decades. Demographic and physiological evidence of adaptation in one heavily affected species, Myotis lucifugus, has prompted multiple attempts to delineate the genomic underpinnings, but these studies show little congruence in their findings. This may be due, in part, to the limitations of the genomic resources utilized and/or analytical approaches employed. Here, we performed high-coverage whole-genome resequencing of M. lucifugus sampled prior to (n = 29), and 10 years after the local arrival of WNS (n = 30), aligned to a new reference genome to identify signatures of selection associated with adaptive responses. Using 41.9 million SNPs, we implemented a combination of hard and soft sweep detection analyses, leading to the discovery of 382 genes with robust evidence of selection. Of these, 202 (49.9%) were associated with enriched gene ontology (GO) terms, many of which were tied to neuron development, organization and function. Further, approximately half (107) of genes associated with enriched GO terms interact with genes identified by previous studies. Our findings suggest reduced susceptibility to WNS is mediated through highly complex, polygenic mechanisms. Further, we demonstrate there are far more connections among WNS selection study results than previously recognized. We believe that the methods employed by our study illustrate a need for a paradigm shift in non-model selection studies and further highlight the value of genomics as a tool for conservation management.