Prion Prospects Researchers are finding that the same mysterious agents responsible for Mad Cow Disease may actually play a beneficial role in some organisms. Find out more about prions. The Official Mad Cow Disease Home Page . Click here for larger image. Prions cause Mad Cow Disease and similar brain-wasting disorders in sheep and humans.
Prions are proteins that are mis-folded.
If you think of a group of standard proteins as resembling paper napkin rings, a prion is like a mobius strip. It's the same protein, but it folds itself in a different way. This rogue shape somehow carries instructions normally carried by a genetic code. Jonathan Weissman of the University of California at San Francisco studies prions in common Baker's Yeast. There's actually no disadvantage for the yeast to have a prion in it.