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The spinocerebellar ataxias

Puneet Opal, MD, PhD
Huda Y Zoghbi, MD
Section Editors
Marc C Patterson, MD, FRACP
Helen V Firth, DM, FRCP, DCH
Deputy Editor
John F Dashe, MD, PhD


Numerous classification systems have been proposed for the autosomal dominant ataxias, which are distinct from the autosomal recessive disorder, Friedreich ataxia. (See "Friedreich ataxia".)

One system proposed by Anita Harding divided these disorders into autosomal dominant cerebellar ataxia types I, II, and III [1,2]:

Type I syndromes are ataxias with ophthalmoplegia, optic atrophy, dementia and extrapyramidal features (ie, SCA1-SCA4, SCA8, SCA10, SCA12-SCA23, SCA25, SCA27, SCA28, and dentatorubral pallidoluysian atrophy or DRPLA)

Type II ataxias are associated with pigmented maculopathy with or without ophthalmoplegia or extrapyramidal features (ie, SCA7)

Type III syndromes are pure ataxic syndromes (ie, SCA5, SCA6, SCA11, SCA26, SCA29, SCA30, and SCA31)


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Literature review current through: Sep 2016. | This topic last updated: Jan 7, 2016.
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