Spinocerebellar Ataxia Type 2

  • Daniel R. Scoles
  • Stefan M. Pulst
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 1049)


Spinocerebellar ataxia type 2 (SCA2) is autosomal dominantly inherited and caused by CAG repeat expansion in the ATXN2 gene. Because the CAG repeat expansion is localized to an encoded region of ATXN2, the result is an expanded polyglutamine (polyQ) tract in the ATXN2 protein. SCA2 is characterized by progressive ataxia, and slow saccades. No treatment for SCA2 exists. ATXN2 mutation causes gains of new or toxic functions for the ATXN2 protein, resulting in abnormally slow Purkinje cell (PC) firing frequency and ultimately PC loss. This chapter describes the characteristics of SCA2 patients briefly, and reviews ATXN2 molecular features and progress toward the identification of a treatment for SCA2.


Spinocerebellar ataxia type 2 Ataxin-2 Neurodegeneration Cerebellum 



We thank Duong P. Huynh and Sharan Paul for editing the chapter. We thank Darren Ames and Lance Pflieger for assistance with transcriptome analysis computations.


This work was supported by the Carmen and Louis Warschaw Endowment Fund, the National Ataxia Foundation, grants R01NS33123, R56NS33123 and R37NS033123 from the National Institutes of Neurological Disorders and Stroke to SMP, the Noorda foundation to SMP, and grants RC4NS073009 and R21NS081182 to DRS and SMP. SMP received grant support from the Target ALS Foundation.

Conflict of Interest Statement

SMP is a consultant for Progenitor Life Sciences.


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© Springer International Publishing AG 2018

Authors and Affiliations

  1. 1.Department of NeurologyUniversity of UtahSalt Lake CityUSA

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