Identification of a novel ovine PrP polymorphism and scrapie-resistant genotypes for St. Croix White and a related composite breedSeabury C.M. · Derr J.N.
Department of Veterinary Pathobiology, College of Veterinary Medicine, Texas A&M University, College Station TX (USA)
Susceptibility to scrapie is primarily controlled by polymorphisms in the ovine prion protein gene (PRNP). Here, we report a novel ovine exon three PRNP polymorphism (SNP G346C; P116), its association with the ovine ARQ allele (P116A136R154Q171), and two new genotypes (PARQ/ARR; PARQ/ARQ) for the St. Croix White (SCW) breed and a related composite (CMP) breed developed for meat production. The (P116) polymorphism occurs between the N-terminal cleavage site and the hydrophobic region of the ovine prion protein, a region which exhibits extreme conservation across mammalian taxa. The relatively high frequency (0.75) of resistant ARR alleles and the absence of ARQ alleles for the SCW ewes used as breeding stock for CMP resulted in significant genic differentiation (P = 0.0123; S.E. = 0.00113). Additionally, the majority of the SCW (66.7%) and CMP (65.4%) sampled possessed genotypes considered resistant or nearly resistant to scrapie and experimental BSE (bovine spongiform encephalopathy.
© 2003 S. Karger AG, Basel
Supported by Texas A&M University and the Texas Agricultural Experimnent Station.
Received 25 May 2003;
manuscript accepted 30 July 2003.
Number of Print Pages : 4
Number of Figures : 1, Number of Tables : 1, Number of References : 25
Cytogenetic and Genome Research
Formerly ‘Cytogenetics and Cell Genetics’
Vol. 102, No. 1-4, Year 2003 (Cover Date: 2003)
Journal Editor: H.P. Klinger, Bronx, N.Y.; M. Schmid, Würzburg
ISSN: 1424–8581 (print), 1424–859X (Online)
For additional information: http://www.karger.com/journals/cgr