The transcription, synthesis, intracellular transport and activity-dependent release of brain-derived neurotrophic factor (BDNF) are all impaired in a number of neurological disorders, including RTT and Huntington's disease (Gines et al., 2010; Hartmann et al., 2012; Li and Pozzo-Miller, 2014; Tapia-Arancibia et al., 2008). Here, BDNF is linked to nervous system disorder.