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Neurological channelopathies
Neurological channelopathy refers to disorders of ion channels which affect the function of nerves. These disorders can result from either gain of function or loss of function of certain ion channels, often associated with heritable autoimmune diseases.

Examples include Episodic ataxia type 1(EA1), which is a kind of potassium channelopathy discovered in 1975, causes neuromyotonia and myokymia by limiting nerve excitability. Another example is Episodic ataxia type 2(EA2), a rare autosomal dominant neurological disorder caused by voltage-gated calcium channel dysfunction. EA 2 is most commonly caused by a functional deletion mutation in the calcium channel gene CACNA1A, which encodes the Ca(v)2.1 subunit of the P/Q-type calcium channel and is mainly expressed in Purkinje cells.