Creutzfeldt-Jakob disease associated with a deletion of two repeats in the prion protein gene.

A two-octapeptide repeat deletion of the prion protein gene has been recently observed in a patient with a 2-year history of dementia and a clinical diagnosis of possible Creutzfeldt-Jakob disease (CJD). The authors report a similar deletion in a patient with a definitive diagnosis of CJD. Since the two-repeat deletion has not been observed in large, population-based studies, the two cases suggest that this deletion is a new pathogenic mutation associated with CJD.