PSEN1 and dementia: For instance, by employing florbetapir PET analyses, Fleisher et al. showed that individuals from the Antioquia cohort carrying the PSEN1 E280A mutation showed evident accumulation of fibrillar Aβ at a mean age of 28.2 years, which was approximately 16 and 21 years before the expected MCI and dementia onset, respectively [44].