Episodic Ataxia/Myokymia

Browne DL, Gancher ST, Nutt JG et al 1994 Episodic ataxia/myokymia syndrome is associated with point mutat ions in the human potassium channel gene, KCNAl. Nat Genet 8 136-140... 

Episodic ataxia (EA) is an autosomal dominant disorder that brief episodes of ataxia can be triggered by physical or emotional stress. The symptom can occur several times during the day, last for seconds to minutes, and be associated with dysarthria and motor neuron activity, which causes muscle rippling (myokymia) between and during attacks. It is caused by a mutation in a neuronal voltage dependent Ca2+ channel. 

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