Importantly, DYRK1A overdosage accelerates the onset of AD in DS adults (Liu et al., 2008; Lowe et al., 2019; Wegiel et al., 2008, 2011b), lowering the mean age of appearance to 50–54 years old (Larsen et al., 2024) and increasing its prevalence to 90–100% in this population (Fortea et al., 2021). This evidence concerns the gene DYRK1A and Alzheimer disease.