In the previously reported tubulin-related lissencephaly cases, the cortical plate was either two-layered with virtually absent normal laminar organization or four-layered, coexisting with a band of ectopic neurons of diverse shape and size organized in columns or clusters, lying in a reduced rim of white matter reminiscent of LIS1 related lissencephaly. Here, PAFAH1B1 is linked to lissencephaly spectrum disorders.