Identification of putative atypical scrapie in sheep in Portugal
Leonor Orge1,2, Alexandre Galo1, Carla Machado1, Carla Lima1, Cristina
Ochoa1, João Silva1, Manuel Ramos1 and J. Pedro Simas2,3
1 Laboratório Nacional de Investigação Veterinária, Lisboa, Portugal
2 Instituto Gulbenkian de Ciência, Rua da Quinta Grande 6, 2780-156
Oeiras, Portugal
3 Laboratório de Microbiologia, Faculdade de Medicina, Universidade de
Lisboa, Lisboa, Portugal
Correspondence
J. Pedro Simas
jpsimas@igc.gulbenkian.pt
Experimental transmission of bovine spongiform encephalopathy to sheep
has prompted the implementation of a surveillance plan of scrapie in
small ruminants by the European Union in all member states. Since its
start over 30 000 animals have been tested, and the first seven cases of
sheep with detectable PrPres deposition in the central nervous system
have been identified in Portugal. Notably, the pattern of PrPres
distribution in the brainstem was different from that previously
described for scrapie and consistent in all seven animals. Moreover, the
profile of the electrophoretic mobility of PrPres after proteinase K
treatment was equivalent in all cases analysed but distinct from that
observed for scrapie. Notably, four animals had genotypes rarely
associated with scrapie, including one animal homozygous for
A136R154R171. There were no cases found to exhibit vacuolation, a
pattern of PrPres distribution or PrPres electrophoretic mobility
corresponding to scrapie. These data reveal a putative atypical scrapie
strain in Portugal not linked to specific Prnp genotypes.
http://vir.sgmjournals.org/cgi/content/abstract/85/11/3487?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=prion&searchid=1097700246431_1433&stored_search=&FIRSTINDEX=0&volume=85&issue=11&search_url=http%3A%2F%2Fvir.sgmjournals.org%2Fcgi%2Fsearchtss
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