Molecular basis of neuronal migration disorders
Janusz Wendorff
Disorders of neuronal migration are a relatively frequent cause of neuropaediatric syndromes such as: epilepsy, cerebral palsy, hydrocephalus, congenital muscular dystrophy and they may coexist with autism and other neurodevelopmental disorders. Migration of neuroblasts depends on genetic regulation, growth factors and it may be destroyed by some environmental factors such as virus infections. Some proteins, products of genes, included in the migration process are responsible for particular phase of migration, such as: filamin, double-cortin, LIS1, fucutin, astrotactin and reelin. The author describes some neuropaediatric syndromes associated with protein missing in the migration phase of neurodevelopment. The most frequent disorder is lissencephaly with its four genetic types: isolated lissencephaly (ILS), Miller-Dieker syndrome (MDS), X-linked lissencephaly and subcortical laminar heterotopia (XLIS). Mutation in the doublecortin gene leads to “double cortex” syndrome, which affects females and most frequently causes drug-resistant epilepsy and mental retardation of different severity. Fukuyama muscular dystrophy (FMD) belongs to syndromes associated with the final phase of neuronal migration. FMD manifests general muscular hypotonia, joint contractures, cerebral and cerebellar cortical malformations, cortical dysplasia with X-linked hydrocephalus. In the final part of the study the author presents own results concerning the course of early-infantile epilepsy in malformations of cortical development.