Inherited ion channel disorders

The inherited ion channel disorders (channelopathies) are a group of disord ers caused by mutations in genes encoding ion channels. Ion channel disorde rs can affect any tissue, but the majority affect skeletal muscle or the ce ntral nervous system. These disorders include skeletal muscle sodium channe lopathies causing hyperkalaemic periodic paralysis, paramyotonia congenita and potassium-aggravated myotonia. Skeletal muscle calcium channelopathies can cause hypokalaemic periodic paralysis, malignant hyperthermia and centr al core disease. Skeletal muscle chloride channelopathies can cause Thomsen and Becker myotonia. A neuronal sodium channelopathy causes the generalise d epilepsy febrile seizures plus syndrome. Neuronal potassium channelopathi es can cause familial benign neonatal convulsions and episodic ataxia type 1. Finally, neuronal calcium channelopathies can cause episodic ataxia type 2, familial hemiplegic migraine and spinocerebellar ataxia type 6. Conclusion The clinical features, aetiology and pathogenesis of inherited v oltage-gated ion channel disorders affecting muscle and the central nervous system are reviewed here.