Chronic wasting disease in Norway—A survey of prion protein gene variation among cervids

Abstract

Susceptibility of cervids to Chronic Wasting Disease (CWD), a prion disease, can be modulated by variations in the prion protein gene (PRNP), encoding the cellular prion protein (PrPC). In prion diseases, PrPC is conformationally converted to pathogenic conformers (PrPSc), aggregates of which comprise infectious prions. CWD has recently been observed in its contagious form in Norwegian reindeer (Rangifer tarandus) and in novel, potentially sporadic forms, here called ‘atypical CWD’, in moose (Alces alces) and red deer (Cervus elaphus). To estimate relative susceptibility of different Norwegian cervid species to CWD, their non‐synonymous PRNP variants were analyzed. In reindeer, seven PRNP alleles were observed and in red deer and moose two alleles were present, whereas roe deer (Capreolus capreolus) PRNP was monomorphic. One ‘archetypal’ PRNP allele associated with susceptibility was common to all four cervid species. The distribution of PRNP alleles differed between wild and semi‐domesticated reindeer, with alleles associated with a high susceptibility occurring, on average, above 55% in wild reindeer and below 20% in semi‐domesticated reindeer. This difference may reflect the diverse origins of the populations and/or selection processes during domestication and breeding. Overall, PRNP genetic data indicate considerable susceptibility to CWD among Norwegian cervids and suggest that PRNP homozygosity may be a risk factor for the atypical CWD observed in moose. The CWD isolates found in the Norwegian cervid species differ from those previously found in Canada and USA. Our study provides an overview of the PRNP genetics in populations exposed to these emerging strains that will provide a basis for understanding these strains’ dynamics in relation to PRNP variability.

Monitoring of chronic wasting disease (CWD) (IV)

“…In roe deer, this is the only observed PRNP allele. Thus, they appear to be monomorphic for the wt‐allele (Peletto et al., 2009 ; Wik et al., 2012 ; Robinson et al., 2019 ; Güere et al., 2022 ).…”

Transport of Prions in the Peripheral Nervous System: Pathways, Cell Types, and Mechanisms

“…Recently, CWD cases have been identified in Norway, Sweden, and Finland. Compared to North American CWD, the Scandinavian CWD cases have PrP Sc and transmission properties suggesting that it is a unique strain of CWD [ 24 , 62 , 63 , 64 , 65 , 66 , 67 ]. Notably, CWD prions persist in the environment and are highly contagious resulting in horizontal transmission in both captive and free-ranging cervid populations [ 24 , 25 , 68 ].…”

Association Study of the M132L Single Nucleotide Polymorphism With Susceptibility to Chronic Wasting Disease in Korean Elk: A Meta-Analysis

“…Prion diseases are infectious brain proteinopathies caused by a pathogenic form of prion protein (PrP Sc ) converted from an endogenous form of prion protein (PrP C ) and are classified into several types in a wide range of mammalian hosts: Creutzfeldt-Jakob disease (CJD), fatal familial insomnia (FFI) and Gerstmann-Sträussler-Scheinker syndrome (GSS) in humans; scrapie in sheep and goats; bovine spongiform encephalopathy (BSE) in cattle; and chronic wasting disease (CWD) in the Cervidae family (1)(2)(3)(4)(5)(6)(7). After CWD was first reported in mule deer in the USA in the 1967, CWD has been reported globally, including in North America, South Korea and Scandinavia, in variable cervid species, such as white-tailed deer, elk, moose, red deer and reindeer (8)(9)(10)(11). To date, CWD is a fatal and incurable disorder, and its exact origin has not been elucidated to date.…”