The examination of brains from adult individuals with DS taken post mortem from the temporal, frontal and parietal cortex and brains from Ts65Dn mice (12–22 months), as well as primary cultures of cortex foetal brains from individuals with DS (17–21 gestational age weeks) revealed, similar to Alzheimer’s disease, that the synthesis of NGF is not affected and there is an abundance of the NGF precursor, proNGF. This evidence concerns the gene NGF and Dravet syndrome.