NR AOUF
AU Houston,E.F.; Goldmann,W.; Chong,A.; Jeffrey,M.J.; Gonzalez,L.; Hunter,N.
TI Effect of PrP genotype on susceptibility to BSE in sheep
QU International Conference - Prion diseases: from basic research to intervention concepts - TSE-Forum, 08.10.-10.10.2003, Gasteig, München - Poster session - PG-17
PT Konferenz-Poster
AB Polymorphisms of the sheep PrP gene at codons 136, 154 and 171 have been linked to enhanced susceptibility or resistance to scrapie. Susceptibility to scrapie is strongly associated with V at position 136 and/or Q at position 171. The ARR allele is associated with resistance to natural scrapie, and in homozygous sheep only one unconfirmed scrapie case has been reported world-wide among animals exposed by natural and experimental routes. In sheep experimentally challenged with BSE, the shortest incubation periods have been recorded in ARQ/ARQ homozygotes. However, very small numbers of sheep with other PrP genotypes have been tested, and in sheep carrying the VRQ allele results were confounded by the presence of natural scrapie. In this study we investigated the effect of PrP genotype on susceptibility to BSE, using larger groups of New Zealand sheep of six different PrP genotypes challenged by the intracerebral route. Interim results show transmission to ARQ/ARQ, VRQ/VRQ, VRQ/ARQ and ARR/ARR sheep, but not to ARR heterozygotes. Analysis of tissues from these sheep will help to establish whether PrP genotype influences the strain characteristics of BSE, an important issue for surveillance schemes attempting to detect BSE in the sheep population. The transmission of BSE to ARR/ARR sheep also raises questions about the basic mechanisms underlying genetic resistance, and may have implications for scrapie control and eradication policies based on selective breeding to increase the frequency of the ARR allele.
AD F. Houston, W. Goldmann, A. Chong, N. Hunter, Institute for Animal Health, UK; M. Jeffrey, L. González, Veterinary Laboratories Agency - Lasswade, UK
SP englisch
PO Deutschland