Neurobiology of Huntington’s Disease

Chapter
Part of the Current Topics in Behavioral Neurosciences book series (CTBN, volume 22)

Abstract

Of the neurodegenerative diseases presented in this book, Huntington’s disease (HD) stands as the archetypal autosomal dominantly inherited neurodegenerative disorder. Its occurrence through generations of affected families was noted long before the basic genetic underpinnings of hereditary diseases was understood. The early classification of HD as a distinct hereditary neurodegenerative disorder allowed the study of this disease to lead the way in the development of our understanding of the mechanisms of human genetic disorders. Following its clinical and pathologic characterization, the causative genetic mutation in HD was subsequently identified as a trinucleotide (CAG) repeat expansion in the huntingtin (HTT) gene, and consequently, the HTT gene and huntingtin protein have been studied in great detail. Despite this concentrated effort, there is still much about the function of huntingtin that still remains unknown. Presented in this chapter is an overview of the current knowledge on the normal function of huntingtin and some of the potential neurobiologic mechanisms by which the mutant HTT gene may mediate neurodegeneration in HD.

Keywords

Huntington’s disease Neurodegeneration Huntingtin Disease mechanisms 

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© Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Centre for Molecular Medicine and Therapeutics, Department of Medical Genetics, Child and Family Research InstituteUniversity of British ColumbiaVancouverCanada

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