DCX-related disorders include the neuronal migration disorders classic lissencephaly (formerly also known as lissencephaly type 1), usually in males; and subcortical band heterotopia (SBH, also called double cortex), primarily in females. Males with classic DCX-related lissencephaly typically have severe and global developmental delay, infantile-onset seizures (infantile spasms, West syndrome, focal and generalized seizures), and severe intellectual disability. In individuals with SBH, cognitive abilities range from normal to learning disabilities and/or severe intellectual disability. The majority of individuals with SBH present with focal or generalized seizures. Behavior problems may also be observed. In DCX-related lissencephaly and SBH the severity of the clinical manifestation correlates with the degree of the underlying brain malformation.
Diagnosis/testing.…show more content… The diagnosis is confirmed by molecular genetic testing. The DCX-related lissencephaly presents as classic lissencephaly and is characterized by absent gyri (agyria) or reduced gyration (pachygyria) with thickened cortex. Molecular genetic testing of DCX should include sequence analysis including all coding exons and exon-intron boundaries in combination with a specific method (e.g., MLPA) to identify exonic deletions or