Polyalanine Tract Disorders and Neurocognitive Phenotypes

  • Cheryl ShoubridgeEmail author
  • Jozef Gecz
Part of the Advances in Experimental Medicine and Biology book series (AEMB)


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.


Tandem Repeat Polymorphism Cleidocranial Dysplasia Oculopharyngeal Muscular Dystrophy Polyalanine Tract Ohtahara Syndrome 
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© Landes Bioscience and Springer Science+Business Media 2012

Authors and Affiliations

  1. 1.Department of Genetics and Molecular PathologySA Pathology at the Women’s and Children’s HospitalNorth AdelaideAustralia
  2. 2.Department of PediatricsUniversity of AdelaideAdelaideAustralia

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