NR ABCK
AU Baylis,M.; Houston,E.F.; Goldmann,W.; Hunter,N.; McLean,A.R.
TI The signature of scrapie: differences in the PrP genotype profile of scrapie-affected and scrapie-free UK sheep flocks.
QU Proceedings of the Royal Society B: Biological Sciences 2000 Oct 22; 267(1457): 2029-35
IA http://www.journals.royalsoc.ac.uk/media/mh9xd63l8m0rwhbd1kdr/contributions/n/l/4/f/nl4ff8wge62nkw9x.pdf
PT journal article
AB The amino-acid sequence of the PrP protein plays an important role in determining whether sheep are susceptible to scrapie. Although the genetics of scrapie susceptibility are now well understood, there have been few studies of the PrP gene at the population level, especially in commercially farmed sheep. Here we describe the PrP genetic profiles of the breeding stock of four UK sheep flocks, comprising nearly 650 animals in total. Two flocks had been scrapie affected for about eight years and two were scrapie free. Scrapie-resistant PrP genotypes predominated in all flocks but highly susceptible genotypes were present in each case. The distribution of PrP genotypes was similar in the scrapie-affected and scrapie-free flocks. The former, however, showed a slight but significant skew towards more susceptible genotypes despite their previous losses of susceptible sheep. Surprisingly, this skew was apparent in younger, but not older, sheep. We suggest that these patterns may occur if sheep flocks destined to become scrapie affected are predisposed by a genetic profile skewed towards susceptibility. The age structure of the scrapie-affected flocks suggests that the number of losses attributable directly or indirectly to scrapie considerably exceeds that recognized by the farmers, and also that significant losses may occur even in sheep of a moderately susceptible genotype. Similar patterns were not detected in the scrapie-free flocks, indicating that these losses are associated with scrapie infection as well as genotype.
MH Age Factors; Animals; Base Sequence; DNA Primers/genetics; Gene Frequency; Genetics, Population; Genotype; Great Britain; Prions/*genetics; Research Support, Non-U.S. Gov't; Scrapie/*genetics; Sheep
AD Matthew Baylis (matthew.baylis@bbsrc.ac.uk), E. Fiona Houston (fiona.houston@bbsrc.ac.uk), Institute for Animal Health, Compton Laboratory, Compton, Newbury, Berkshire RG20 7NN, UK; Wilfred Goldmann (wilfred.goldmann@bbsrc.ac.uk), Nora Hunter (nora.hunter@bbsrc.ac.uk), Institute for Animal Health, BBSRC and MRC, Neuropathogenesis Unit, Ogston Building, West Mains Road, Edinburgh EH9 3JF, Scotland, UK; Angela R. McLean, Department of Zoology, University of Oxford, South Parks Road, Oxford, OX1 3PS, UK
SP englisch
PO England