chapter  76
Huntington’s disease
ByPhyllis Chua, Samantha Loi, Edmond Chiu
Pages 17

Huntington’s disease (HD) is an autosomal-dominant progressive neurodegenerative disorder beginning classically in midlife with the characteristic triad of motor, cognitive and psychiatric symptoms. Within this characteristic triad, there is variety in the clinical phenotype with respect to timing of onset, symptoms and progression. Death usually occurs 20-30 years aer the onset of motor symptoms. Discovery of the HD gene in 1993 has changed our understanding of the natural history of HD with recognition of preclinical manifestations and early symptoms prior to the classical motor manifestations.