Abstract

Researchers in Italy have identified a novel form of bovine spongiform encephalopathy (mad cow disease) in two seemingly healthy cows that could further our understanding of human diseases such as Creutzfeldt-Jakob disease. But others say that the findings reported in the February 17 online PNAS do not necessarily provide insights in human manifestations of the disease. Cristina Casalone and colleagues at the Centro di Referenza Nazionale per le Encefalopatie Animali in Turin report that more than one prion strain may be responsible for bovine spongiform encephalopathy (BSE). The molecular signature of the newly discovered strain, combined with its corresponding brain deposition and disease pathology bear striking similarities to sporadic Creutzfeldt-Jakob disease (sCJD) in humans (PNAS ref). Michael Coulthart, director of the Prion Diseases Program at the National Microbiology Laboratory with Health Canada, cautions against prematurely assuming there is a correlation. “The connection between these novel phenotypes of BSE and something going on in human sCJD is so far unproven.” Transmissible spongiform encephalopathies (TSEs) in humans can be sporadic, acquired, or inherited diseases. Sporadic (or spontaneous) TSE is the most common, occurring in roughly one in a million individuals. Symptoms of sporadic and inherited TSEs do not appear until