Our finding that mnb overexpression causes age-related neurodegeneration confirms previous studies inferring a link between DYRK1A overexpression and degeneration and loss of neurons (Duchon and Herault, 2016; García-Cerro et al., 2017; Watson-Scales et al., 2018; Wegiel et al., 2008), which is associated with faster age-related decline in motor and cognitive function in DS and AD-DS. This evidence concerns the gene DYRK1A and Alzheimer disease.