HUNTINGTON'S DISEASE

Huntington's Disease

Huntington's Disease

Description

Huntington's disease, chorea, or disorder (HD), is an incurable neurodegenerative genetic disorder that affects muscle coordination and some cognitive functions, typically becoming noticeable in middle age. It is the most common genetic cause of abnormal involuntary writhing movements called chorea. It is much more common in people of Western Europe descent than in those from Asia or Africa. The disease is caused by a dominant mutation on either of the two copies of a specific gene, located on chromosome 4. (Kremer 2008)

How it Develops?

Any child of an affected parent has a 50% chance of inheriting the disease. In rare situations where both parents have an affected gene, or either parent has two affected copies, this chance is greatly increased. Physical symptoms of Huntington's disease can begin at any age from infancy to old age, but usually begin between 35 and 44 years of age. On rare occasions, when symptoms begin before about 20 years of age, they progress faster and vary slightly, and the disease is classified as juvenile, akinetic-rigid or Westphal variant HD. (Stelzl et al. 2007)

Signs & Symptoms

Symptoms of Huntington's disease commonly become noticeable between the ages of 35 and 44 years, but they can begin at any age from infancy, often when affected individuals have had children. In the early stages, there are subtle changes in personality, cognition, or physical skills. The physical symptoms are usually the first to be noticed, as cognitive and psychiatric symptoms are generally not severe enough to be recognized on their own at the earlier stages. Almost everyone with Huntington's disease eventually exhibits similar physical symptoms, but the onset, progression and extent of cognitive and psychiatric symptoms vary significantly between individuals.

The most characteristic initial physical symptoms are jerky, random, and uncontrollable movements called chorea. Chorea may be initially exhibited as ...