TSC2 and autism: Since the amount and availability of synaptic proteins affect not only synaptic signalling but also the structure and plasticity of neurons, and the fact that changes in synaptic morphology and number are linked to the majority of psychiatric and neurological disorders, from autism to neurodegenerative disorders, a comprehensive ultrastructural analysis of the brains of Tsc2+/− mice using transmission electron microscopy (TEM) was performed.