Chapter 8
Repeat expansion diseases and dementia
Praveen Dayalu, Roger L. Albin,
Henry Paulson,
Roger L. Albin
University of Michigan, Ann Arbor, MI, USA
VAAAHS GRECC, Ann Arbor, MI, USA
Search for more papers by this authorPraveen Dayalu, Roger L. Albin,
Henry Paulson,
Roger L. Albin
University of Michigan, Ann Arbor, MI, USA
VAAAHS GRECC, Ann Arbor, MI, USA
Search for more papers by this authorBook Editor(s):Michael D. Geschwind MD PhD,
Caroline Racine Belkoura PhD,
Michael D. Geschwind MD PhD
Memory and Aging Center, Department of Neurology, University of California, San Francisco, San Francisco, CA, USA
Search for more papers by this authorCaroline Racine Belkoura PhD
Department of Neurological Surgery, University of California, San Francisco, San Francisco, CA, USA
Search for more papers by this authorFirst published: 22 January 2016
Summary
More than 20 neurologic disorders are caused by DNA repeat expansions. In most, dementia is not prominent. Huntington's disease (HD), the most common polyglutamine repeat disorder, is a notable exception. It is a devastating neurodegenerative disease that causes dementia, psychiatric disease, and motor symptoms including chorea. HD is progressive and leads to death in about 20 years. Symptomatic treatments exist for chorea and psychiatric disease in HD, but not for cognitive symptoms. SCA17 is the spinocerebellar ataxia in which dementia is very common and an early feature. Fragile X-associated tremor/ataxia syndrome (FXTAS) causes cognitive decline in addition to tremor and ataxia.
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