MAPT and Alzheimer disease: Although our patient sample corresponds to probable AD with increased level of certainty, due to repetitive clinical visits with no change in diagnosis, documented cognitive decline, and congruent MRI findings [21], an amyloid and tau positivity as claimed by Jack et al. [50] was not available in a considerable portion of study participants and, therefore, the presence of other forms of neurodegenerative dementia cannot be entirely excluded.