APP and Dravet syndrome: Down syndrome (DS), one of the most frequent neurodevelopmental disorders,1 caused by an extra copy of the chromosome 21, presents with variable degrees of behavioural, cognitive and motor impairments.2 The interaction between neurodevelopmental and neurodegenerative pathology, including deficient neurogenesis and synaptogenesis,3-6 impaired myelination,7,8 amyloid precursor protein overproduction9 and immuno-metabolic dysfunction,10 to name but a few, provides a framework for interpreting the observed interindividual and age-dependent variability in the clinical presentation of DS.