Heterozygosity for a TOR1A mutation causes semi-penetrant childhood-onset dystonia. More recently, homozygous TOR1A mutations were shown to cause severe neurological dysfunction in infants. However, there is little known about this disease, including whether reported cases define the full spectrum of symptoms. Here we describe abnormal brain morphogenesis in ~30% of Tor1a-/- embryos. These brains contain excess neural tissue, as well as proliferative zone cytoarchitectural defects related to radial glial cell polarity and cytoskeletal organization. In cultured cells, torsinA effects the LINC complex that couples the nucleus and cytoskeleton. Here we identify that torsinA loss elevates LINC complex levels in the proliferative zone, and that genetic reduction of LINC complexes prevents abnormal Tor1a-/- brain development. These data show that homozygous loss of Tor1a affects radial glial cells via a LINC complex mediated mechanism. They also predict a semi-penetrant component to recessive TOR1A disease where morphological abnormalities arise early in embryonic neurodevelopment.