Type 1 lissencephaly due to doublecortin (DCX) gene mutations is a semi-dominant X-linked disease characterized by intellectual deficiency and seizures that are more severe in male patients. The disease is lissencephaly type 1 due to doublecortin gene mutation (MONDO_0010239). Also known as: X-linked lissencephaly type 1, lissencephaly, X-linked, lissencephaly, X-linked, type 1, subcortical laminal heterotopia, X-linked.