Prion diseases BSE in sheep bred for resistance to infection

Selective breeding for disease-resistant genotypes is being pursued as a means of eradicating scrapie (and bovine spongiform encephalopathy (BSE), if it is present) from sheep flocks. Here we show that the genotype associated with the highest resistance can still be infected with BSE by intracerebral inoculation. Although the relevance of this finding to sheep exposed to natural infection remains to be determined, it may have important implications for disease-eradication strategies.