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, or Huntngton's chorea, is a genetic disease that causes selective neural cell death, which results in chorea, or irregular, jerking movements of the limbs caused by involuntary muscle contractions, and dementia. It can cause a lack of concentration and depressi ....

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.... he or she might pass along the gene without even knowing it. The gene for Huntington's disease is located on the short arm of chromosome four in cytogenetic band 4p16.3. It was first identified in 1993. While everyone posseses this gene, in someone suffering from Huntington's disease, the number of repeats of a certain trinucleotide, cytozine-adenine- guanine (CAG), is much larger than what it is in a normal person. In an average person, the number of repeats is between 9 and 37. But is a sufferer of HD, the repeat count is from 37 to 86. While nobody has found a direct correlation between the number of repeats and the age when symptom ....