The Age of Persons Experiencing the Onset of HD Can Vary
People with HD show a wide range of symptoms at the onset of the disease. While most people with HD develop the motor symptoms in their forties and fifties, subtle changes may arise much earlier. Knowledge of the typical age of onset sometimes leads physicians to miss the diagnosis, mistakenly believing the person to be too old or too young to develop HD. About 10% have onset of motor symptoms after age 60 and 10% have Juvenile onset HD, where symptoms manifest before age 20.