Chronic wasting disease (CWD) agents are shed into biological samples, facilitating their horizontal transmission between cervid species. Once prions enter the environment, binding of PrP CWD by soil particles may maintain them near the soil surface, posing a challenge for decontamination. A 2 N sodium hydroxide (NaOH) or 2% sodium hypochlorite (NaClO) solution is traditionally recommended for prion decontamination of equipment and surfaces. Using protein misfolding cyclic amplification with beads and a bioassay with TgElk mice, we compared the effects of these disinfectants in CWD-contaminated soil for 1 or 16 h to those of controls of known infectious titres. Our results suggest that 2 N NaOH in a 1/5 farm soil volume provides a large decrease (>10 2-fold) in prion infectivity.

Prion diseases are transmissible spongiform encephalopathies caused by deleterious prion protein (PrP Sc ) derived from normal prion protein (PrP C ), which is encoded by the prion protein gene (PRNP). We performed an in-depth examination to detect PrP Sc by using enzyme immunoassay (EIA), real-time quaking-induced conversion reactions (RT-QuIC) and protein misfolding cyclic amplification (PMCA) in nine brain tissues derived from three Holstein cattle carrying the E211K somatic mutation of the bovine PRNP gene. The EIA, RT-QuIC and PMCA analyses were not able to detect the PrP Sc band in any tested samples. To the best of our knowledge, this report is the first to describe an in-depth examination of PrP Sc in cattle carrying the E211K somatic mutation of the bovine PRNP gene.

Chronic wasting disease (CWD) is a deleterious brain proteinopathy caused by a pathogenic form of prion protein (PrPSc), which is converted from a benign form of prion protein (PrPC) encoded by the prion protein gene (PRNP). In elk, the M132L single nucleotide polymorphism (SNP) of the PRNP gene likely plays a pivotal role in susceptibility to CWD. However, the association of the M132L SNP with susceptibility to CWD has not been evaluated in Korean elk to date. To estimate the association of the M132L SNP with susceptibility to CWD in Korean elk, we investigated the genotype and allele frequencies of the M132L SNP by amplicon sequencing and performed association analysis between CWD-positive and CWD-negative elk. In addition, we performed a meta-analysis to evaluate the association between the M132L SNP and susceptibility to CWD in quantitatively synthesized elk populations. Furthermore, we estimated the effect of the M132L SNP on elk PrP using in silico programs, including PolyPhen-2, PROVEAN, AMYCO and Swiss-PdbViewer. We did not identify a significant association between the M132L SNP of PRNP and susceptibility to CWD in Korean elk. The meta-analysis also did not identify a strong association between the M132L SNP of PRNP and susceptibility to CWD in quantitatively synthesized elk populations. Furthermore, we did not observe significant changes in structure, amyloid propensity or electrostatic potential based on the M132L SNP in elk PrP. To the best of our knowledge, this was the first report of an association analysis and meta-analysis in Korean elk and quantitatively synthesized elk populations, respectively.

In-Soon Roh and Yong-Chan Kim have contributed equally to this work.

Cervus canadensis nannodes (Merriam, 1905) is one of the subspecies of elk distributed only in California, USA. We completed the first mitogenome of C. canadensis nannodes. Its length is 16,428 bp, which is in middle among 24 available Cervus mitogenomes. It contains 37 genes (13 protein-coding genes, 2 rRNAs, and 22 tRNAs). Phylogenetic trees show that C. c. nannodes was clustered with some subspecies of C. elaphus. Number of inter-subspecific variations between C. c. nannodes and C. e. alxaicus are relatively small in comparison to intraspecific variations of insect and fish mitogenomes and plant chloroplast genomes.