DYRK1A and trisomy 21: Furthermore, in a mouse model of Trisomy 21 (segmental trisomy 16/Ts65Dn mice), overexpression of Dyrk1a by 1.5‐fold echoes phenotypes of Trisomy 21 observed in humans [131, 197, 212, 213, 269, 272, 273], thus supporting the notion that elevated DYRK1A may underpin neurodevelopmental abnormalities associated with Trisomy 21.