In line with this, bacterial artificial chromosome (BAC) transgenic mice carrying an extra copy of Dyrk1a show alteration in brain size and neuronal density [22] together with neurodevelopmental delays, motor abnormalities, altered synaptic plasticity, learning and memory deficits (Table 1), thus recapitulating most of the DS phenotype [23,24,25]. The gene discussed is DYRK1A; the disease is Dravet syndrome.