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Overview of the hereditary 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


The hereditary ataxias are a genetically heterogeneous group of diseases that may be difficult to distinguish clinically because they are all characterized by motor incoordination resulting from dysfunction of the cerebellum and its connections [1]. With the identification of the gene defects in many of these disorders, the diagnosis now is made more often by genetic testing.

The hereditary ataxias have traditionally been divided into two main classes:

Ataxia caused by underlying inborn errors of metabolism; these disorders usually are inherited in an autosomal recessive manner and typically present in childhood.

Progressive degenerative ataxias not due to inborn errors of metabolism. This group of disorders, which are more common, are divided by their mode of inheritance into autosomal dominant, autosomal recessive, X-linked, and mitochondrial forms.

The hereditary ataxias caused by inborn errors of metabolism and the episodic, X-linked, and mitochondrial ataxias are discussed in this topic.

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Literature review current through: Nov 2017. | This topic last updated: Mar 17, 2017.
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