PRNP and kuru: The origins of kuru have remained somewhat obscure; however, in the absence of a pathogenic PRNP mutation associated with kuru (Lee et al. 2001; Mead et al. 2003), or any evidence for an animal origin, the most plausible hypothesis for the source of kuru is through chance consumption of an individual with sporadic CJD (Alpers & Rail 1971).