In order to investigate the role of UBE3A in neuronal contact guidance and to explore neuronal morphological aspects relevant for its imbalance in AS and Dup15q autism, we exploited micrograting (GR) substrates with a grooved pattern of 1-μm ridge, 1-μm groove, and 500-nm depth (Fig. 1a, b), which transfer a directional impulse to neuronal cells by contact interaction [5]. Here, UBE3A is linked to autism.