Genetics of infantile nervous system channelopathies

Channelopathies may present in infantile and childhood periods as paroxysmal disorders with different manifestations in neurologic, cardiac and neuromuscular system. These channelopathies include genes encoding voltage-gated channels specific for sodium (SCN1A, SCN2A, SCN1B, SCN9A) and potassium (KCNQ2, KCNQ3) which account for a variety of epilepsy phenotypes ranging from mild, such as Benign familial neonatal seizures (BFNS) to severe, such as Dravet syndrome (severe myoclonic epilepsy of infancy, SMEI) and the rare and unusual syndrome. Paroxysmal extreme pain disorder (PEPD).Ligand-gated channels involved include the GABAA receptor in a variety of epilepsy phenotypes and the human glycine receptor. Mutations in five genes encoding subunits of this receptor and accessory molecules underlie hyperekplexia or stiff baby syndrome. In this article we have a brief review of these channelopathies and we hope that our readers acquire new concepts of these old diseases, not only for genetic counseling but to allow the specific treatment.