Diversity and selective forces in the key honey bee pathogen, Deformed wing virus

Deformed wing virus (DWV) is an important pathogen of honey bees tied to widespread colony losses. The introduction of the honey bee parasitic mite, Varroa destructor, has impacted both the virulence and the diversity of DWV. Here we use high-throughput RNA sequencing to survey the genetic structure and, for the first time, test the selective forces faced by virulent DWV populations from the mainland United States. To do this, we produced a series of infectious cDNA clones corresponding to major full-length RNA genome variants (GenBank Accession numbers - MG831200 - MG831204) present in a typical virulent Varroa-associated US DWV population. Injections of these clones allowed us to assess infectivity, genetic stability of the clone-derived DWV variants, and interaction between the clones in the infected honey bees.