The deadly Huntington's disease (aka Huntington's chorea or Huntington's disorder--HD) is a degenerative neurological disorder which affects the muscles, eventually causing a lack of physical coordination, mental decline and dementia. There is no known cure. Children born of a parent with Huntington's disease has a 50% chance of acquiring it themselves. Symptoms normally occur in middle age, and they include unusual, involuntary movements (known as chorea).
Pneumonia and heart disease are often symptomatic, and life expectancy after diagnosis is usually no more than 20 years. The famous folk singer, Woody Guthrie, was finally diagnosed with the disease after years of declining health. His son, songwriter Arlo Guthrie, has shown no symptoms of the disease, however.
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