Chapter Details

Pub Date: 26 Oct 2012
Pages: 19
Chapter Category: Cell Biology
Taken from the Book: Tandem Repeat Polymorphisms: Genetic Plasticity, Neural Diversity and Disease
Book Series: Special Books
Edited by: Anthony J. Hannan

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Polyalanine Tract Disorders and Neurocognitive Phenotypes

Cheryl Shoubridge and Jozef Gécz

About this Chapter

Expansion of polyalanine tracts cause at least 9 inherited human diseases. Eight of these nine diseases are due to expansions in transcription factors and give rise to congenital disorders, many with neurocognitive phenotypes. Disease‑causing expansions vary in length depending upon the gene in question, with the severity of the associated clinical phenotype generally increasing with length of the polyalanine tract. The past decade has seen considerable progress in the understanding on how these mutations may arise and the functional effect of expanded polyalanine tracts on the resulting protein. Despite this progress, the pathogenic mechanism of expanded polyalanine tracts contributing to the associated disease states remains poorly understood. Gaining insights into the mechanisms that underlie the pathogenesis of different expanded polyalanine tract mutations will be a necessary step on the path to the design of potential treatment strategies for the associated diseases.

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