(August 2004) Huntington disease (HD) is a rare, progressive and fatal autosomal dominant neurodegenerative disorder, typically of adult onset. In 1872, Dr. George Huntington (1850-1916), a family doctor in the U.S., published the first paper on the disease that he called “Huntington’s chorea” [1]. A chorea is an abnormal, involuntary movement. The name comes from the Greek word chorea, which means dance. In 1983, HD was the first gene mapped to a chromosomal locus using an anonymous marker technique [2]. After a ten-year struggle, during which fundamental strategies of positional cloning were developed, the causative mutation, a CAG trinucleotide repeat…