Overexpression of human DYRK1A, amyloid-β and Tau 0N4R occurs throughout development and adulthood leading to AD-DS pathology and dementia in young adults (Wiseman et al., 2015; Zigman, 2013; Anderson-Mooney et al., 2016; O'Leary et al., 2018). Here, DYRK1A is linked to Alzheimer disease.