Medical researchers in Canada and the United States recently published their joint findings that fatal prion diseases, which include BSE or "mad cow disease," have a hidden signature.

Findings published this month in the peer-reviewed journal, Public Library of Science (PLoS) Pathogens, demonstrate that up to seven months before an animal shows physical signs of having a prion infection, a particular prion protein in the brain was being eradicated. This member of the prion family is known as shadoo protein.

It's a chicken and egg question. Where do the infectious protein particles called prions come from? Essentially clumps of misfolded proteins, prions cause neurodegenerative disorders, such as mad cow/Creutzfeld-Jakob disease, in humans and animals. Prions trigger the misfolding and aggregation of their properly folded protein counterparts, but they usually need some kind of "seed" to get started.