In neocortex, Dag1 expression in radial glia is required for proper migration of neurons, with Dag1 conditional deletion from neuroepithelial cells or radial glia resulting in Type II lissencephaly (Moore et al., 2002; Pawlisz and Feng, 2011; Satz et al., 2008; Satz et al., 2010). The gene discussed is DAG1; the disease is lissencephaly spectrum disorders.