ABSTRACT
Huntington’s Disease (HD) is an autosomal dominant neurodegenerative disorder with an estimated prevalence of 0.5-1 in 10,000 individuals of European descent (1). HD is characterized by the insidious development of motor, cognitive, and psychiatric disturbances with an inexorable progression towards complete disability and eventual death averaging 18 years after the onset of symptoms (2). George Huntington first characterized the cardinal features of the disease that now bears his name in a report published in 1872 (3). This concise treatise outlined the distinctive choreiform movement disorder, the hereditary nature of the chorea, and the frequent association of the chorea with psychiatric disease (‘‘a tendency to insanity and suicide’’). In 1983, the genetic defect in HD was mapped to chromosome
4p16.3 (4), and 10 years later the causative mutation was identified following a massive effort by a collaborative research consortium (5). HD is caused by an expanded CAG trinucleotide repeat sequence in theHD gene encoding for the huntingtin protein.
