DYRK1A and Dravet syndrome: DYRK1A, the mammalian orthologue of Drosophila minibrain kinase (mnb) (Tejedor et al., 1995), encodes a proline/arginine-directed dual-specificity kinase, and is overexpressed both in the brain of trisomic mice and of individuals with DS (Dowjat et al., 2007).