Midwest Fish & Wildlife Conference 2016

AUTHORS: Emma K. Trone*, Western Illinois University; Christopher N. Jacques, Western Illinois University; James T. Lamer, Western Illinois University; Paige Zick, Western Illinois University; Guoqing Lu, University of Nebraska-Omaha; Paul A. Shelton, Illinois Department of Natural Resources

ABSTRACT: Chronic wasting disease (CWD) is a type of transmissible spongiform encephalopathy (TSE) which affects cervid species throughout North America. The disease is both communicable and transmissible and there is no treatment currently available. This research evaluated gene-expression in CWD-infected and non-infected white-tailed deer collected by Illinois Department of Natural Resource game managers during annual population reduction (e.g., sharpshooting) and disease monitoring efforts throughout the CWD-endemic area of northcentral Illinois and established a timeline for RNA viability. We collected tissue (liver and retropharyngeal lymph nodes) samples from 26 hunter-harvested deer in Hancock County, Illinois during the 2015 annual firearm season to estimate RNA stability; tissue samples were sent to the University of Chicago for analysis. Preliminary results show that RNA is stable through a minimum of 24 hours. However, while integrity was stable, quality of the samples was low; average RIN value ranged from 2.84-5.67. Though uncertain, low RIN values may have been associated with variation in RIN values by tissue type, method of storage, internal body temperature and, ambient temperature. We used next generation sequencing (NGS) to analyze tissue samples from CWD-infected deer euthanized by IDNR sharpshooters during winter 2015 (February – March 2015). Specifically, we used the Illumina HiSeq 2500 Sequencing System (Illumina Inc., San Diego, CA, USA) to quantify and map the transcriptomes, and identify novel and known genes from CWD-infected (n=5) and non-infected (n=5) deer. Preliminary results show that 71.5% of liver transcripts, 68.1% of lymph node transcripts can be annotated by the Uniprot database. Identification of differentially expressed genes involved in the pathogenesis of CWD may enable researchers and wildlife managers throughout Illinois to predict the infectious status of harvested deer using gene expression (transcriptome) profiles developed from this study.