Huntington disease: Clinical, genetic, and social aspects

Huntington disease (HD) is a fascinating neurodegenerative disorder whose features straddle the boundaries of psychiatry neurology, and genetics. The clinical symptoms of HE consist of a triad of motor, cognitive, and psychiatric/behavioral disturbances. In 1993, the I-ID Collaborative Research Group identified the gene and the mutation responsible for I-ID. HD was one of the first neurodegenerative disorders discovered to be caused by a novel mutational mechanism known as trinucleotide repeat expansion. Since then, HD has been the model for autosomal dominant neurogenetic disorders. The clinical, pathological, and genetic aspects of the disease are reviewed and some of the questions that remain to be answered by researchers of the 21st century are outlined.