Characterization of the prion protein gene in axis deer (Axis axis) and implications for susceptibility to chronic wasting disease

ABSTRACT

Axis deer (Axis axis) occur both in captivity and free-ranging populations in portions of North America, but to-date, no data exist pertaining to the species’ susceptibility to CWD. We sequenced the prion protein gene (PRNP) from axis deer. We then compared axis deer PrP^C sequences and amino acid polymorphisms to those of CWD susceptible species. A single PRNP allele with no evidence of intraspecies variation was identified in axis deer that indicates axis deer PRNP is most similar to North American elk (Cervus canadensis) PRNP. Therefore, axis deer may be susceptible to CWD. We recommend proactively increasing CWD surveillance for axis deer, particularly where CWD has been detected and axis deer are sympatric with native North American CWD susceptible species.

KEYWORDS:

• Axis axis
• axis deer
• chital
• chronic wasting disease
• prion protein
• prnp
• prp

Acknowledgments

We thank the late Dr. Robert “Bob” Dittmar II, DVM for his insights into this research prior to his tragic and unexpected passing. Thank you to R. Stubblefield and the staff at Llano River Field Station of Texas Tech University for providing housing and meals during the study and for considerable financial and logistical support. We thank private landowners and hunters for donating tissue samples and staff from Texas Parks and Wildlife Department, Hawaii Department of Land and Natural Resources Division of Forestry and Wildlife, Hill Country Alliance, Pulama Lanai, and Texas A&M AgriLife Extension for assisting in coordinating collection and delivery of tissue samples. Thank you to the Biotechnology Resource Center at the Cornell University Institute of Biotechnology and Eurofins Genomics for performing sanger sequencing of our samples and the Texas Tech University High Performance Computing Center for assistance with high-throughput phylogenetic analyses. Funding for this research was provided from the Llano River Field Station at Texas Tech University, the Graduate School at Texas Tech University, the Bricker Endowment Fund, and the Rumsey Research and Development Fund at Texas Tech University. Thanks to 2 anonymous reviewers and the editor for improvements to this manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).