MAPT and Alzheimer disease: While rare genetic early-onset forms of AD are associated with the over-production of abnormal proteins, including Aß and tau (Scheuner et al. 1996; Naj et al. 2017), the more common late-onset Alzheimer’s disease is associated with reduced clearance of Aß from the brain (Mawuenyega et al. 2010; Tarasoff-Conway et al. 2015; Zuroff et al. 2017).