SUBCORTICAL LAMINAR HETEROTOPIA AND LISSENCEPHALY IN 2 FAMILIES - A SINGLE X-LINKED DOMINANT GENE

Neuronal migration disorders can now be recognised by MRT. This paper reports two families in which the mothers had subcortical laminar hete rotopia and four of their children had either similar heterotopia (two girls) or severe pachygyria or Lissencephaly (two boys). Laminar hete rotopia was more evident on MRI T2 weighted images. The patients had m ild to severe epilepsy and mental retardation depending on the extent of cortical abnormalities. In these families, subcortical laminar hete rotopia, pachygyria, and lissencephaly seem to share the same X linked or autosomal dominant gene. No chromosomal abnormalities, especially of chromosome 17, could be identified. For appropriate genetic counsel ling of the family of a child with Lissencephaly or subcortical lamina r heterotopia, MRI should be performed in parents or siblings with men tal retardation or epilepsy.