In DS, trisomy 21 produces lifelong DYRK1A overexpression, evident from early development and sustained across neuronal and astrocytic populations, which disrupts neurodevelopment and predisposes to premature neurodegeneration (Duchon and Herault, 2016; Soppa et al., 2014; Yin et al., 2017). This evidence concerns the gene DYRK1A and Dravet syndrome.