PRNP and Alzheimer disease: A recently published Italian study [10] showed data similar to our observations: the mean age of the CJD/AD cases (71.07 years for our cohort versus 76.1 years for the Italian patients) is strikingly higher than in pure CJD cases; no link was found between the existence of comorbid AD and disease subtype, prion strain, or PRNP genotype; in both cohorts, there were no patients in the “high” level of AD; data from both cohorts showed low Aβ levels in the CSF.