Endogenous retroviruses [ERVs] constitute a unique group of mobile genomic elements that are acquired from a chance infection of a host germ cell by an infectious retrovirus and are vertically passed to viable progeny. ERVs can confer both structural and functional diversity on the genome and hence have the potential to impact host fitness. The evolutionary dynamics of ERV and host near the time of endogenization are of particular interest because fitness consequences on the host attributable to the ERV are better discerned while ERVs are polymorphic in the population. However, evolutionary events during retroviral endogenization have not been investigated, in part because young ERVs are difficult to detect in whole genome sequence data and efforts to find them are typically motivated by disease in the host. We are studying the evolutionary dynamics of the recently described cervid endogenous retroviruses (CrERVs) that have been colonizing the mule deer genome through multiple infection events over the last 200,000 years up to the present. CrERVs are transcriptionally active in animals and no CrERV from these recent epizootics is fixed, resulting in extensive CrERV insertional polymorphism in mule deer from the northwestern US. In this talk, I will present our recent findings detailing the evolutionary history of CrERV in mule deer genomes from different populations and discuss the different CrERV colonisation histories in animals with chronic wasting disease, which is a naturally acquired prion disease in mule deer.
Mary Poss is a Professor of Biology (Eberly College of Science) and Veterinary and Biomedical Sciences (College of Agriculture) at Penn State University. She earned a BSc from Duke University in Zoology and a MS in Biochemistry from the University of New Hampshire. She then went to Ohio State University for her DVM and practiced large animal medicine for a year before returning to Colorado State University to complete a residency in Pathology and then a PhD in Experimental Pathology. Her research initially focused on the pathogenesis of retroviral infections. Since moving to Penn State in 2007, she has expanded these studies to include the impact that retroviruses have on the evolution and molecular biology of host genomes.