This confirms previous studies suggesting a link between misexpression of DYRK1A with eye size and neurodegeneration (Wegiel et al., 2008; Wegiel et al., 2011; Laguna et al., 2013; Duchon and Herault, 2016; García-Cerro et al., 2017; Watson-Scales et al., 2018), which then drives the accelerated decline in motor and cognitive function in DS and AD-DS and shortened lifespan all strongly correlated with such histopathological changes in the brain (Buchman and Bennett, 2011; Choong et al., 2015; Wiseman et al., 2015; Anderson-Mooney et al., 2016; Arbones et al., 2019). Here, DYRK1A is linked to Alzheimer disease.