Episodic ataxias

Episodic ataxias (EAs) are a group of rare autosomal-dominant diseases characterized by recurrent, discrete episodes of ataxia, giddiness, and vertigo. EA1 and EA2 are the most widely recognized of the autosomal-dominant EAs and are caused by dysfunction of neuronal voltage-gated ion channels. There are central and peripheral nervous system manifestations in both conditions. The current classification is based on genetics and actually includes seven distinct subtypes. But these variants other than EA1 and EA2 are rare, some only occurring in single families, and gene mutations have not been identified in all. It is quite likely, however, that the number of phenotypes and mutated genes will grow further.

Nervous system disease

(EA1) KCNA1 [HSA:3736] [KO:K04874]
(EA2) CACNA1A [HSA:773] [KO:K04344]
(EA5) CACNB4 [HSA:785] [KO:K04865]
(EA6) SLC1A3 [HSA:6507] [KO:K05614]

PMID:19650351 (description, gene)

Finsterer J

Ataxias with autosomal, X-chromosomal or maternal inheritance.

Can J Neurol Sci 36:409-28 (2009)
DOI:10.1017/S0317167100007733

PMID:19734086 (description, gene, drug)

Tomlinson SE, Hanna MG, Kullmann DM, Tan SV, Burke D

Clinical neurophysiology of the episodic ataxias: insights into ion channel dysfunction in vivo.

Clin Neurophysiol 120:1768-76 (2009)
DOI:10.1016/j.clinph.2009.07.003