Huntington's disease is a genetic condition that affects certain nerve cells in the brain and causes brain damage. This can lead to disorders in movement, cognition and behavior. Although symptoms of the disease can develop at almost any age, they usually begin when a person is aged between 35 and 55 years old.

Some of the symptoms seen in Huntington's disease are described below:

• Early symptoms of the disease include personality and behavioral changes, although these are often overlooked initially. Mood swings, apathy, anger, difficulty concentrating and loss of short term memory are typical early symptoms. Lack of motivation and drive are also other early behavioural features that may develop and a person with Huntington's may even start to neglect their own self care or hygiene routines.
• The condition can cause uncontrolled facial movements and sudden, abrupt movements of the body and limbs. Such movement disorders are termed “chorea,” after the Greek word for dance. Huntington's disease is one of the main diseases to cause chorea and the condition was originally termed Huntington's chorea. As the disease advances, these movement disorders become more severe and more frequent.
• Depression is another common feature of Huntington's disease and can occur as a reaction to the diagnosis as well as part of the disease's pathology. A persistent low mood, crying and feelings of despair are typical. Obsessive behavioral patterns may also develop and some individuals become schizophrenic.
• A patient's cognitive ability and communication skills such as perception, thought and judgement are affected. Sufferers may find it difficult to organize their thoughts enough to express them in words. Often, they can comprehend what is being said to them but cannot actually acknowledge that they understand or respond properly.
• The disease gradually worsens over a period of between 10 and 20 years and eventually patients require full-time palliative care. Death usually occurs as a result of a secondary cause such as pneumonia, heart failure or infection.