A prion is an infectious protein, an altered form of a normal cellular protein that has lost its normal function, but has acquired the ability to change the normal form into this abnormal (prion) form. This volume reviews the development of the prion concept in the study of scrapie of sheep, kuru and Creutzfeldt-Jakob disease of man and bovine spongiform encephalitis (Mad Cow Disease), and its recent extension to the non-Mendelian elements of Saccharomyces, (PSI) and (URE3).
