Huntington's Disease

HUNTINGTON'S DISEASE IS a hereditary type of chorea, which is a neurological condition that is associated with involuntary and irregular movements caused by movements of various muscle groups. It is a fatal disease and had no known cure before the development of certain stem cell treatments. The disease is named after the American doctor George Huntington, who first described the condition in detail in 1872. In fact, most variables of the disease—type and severity of symptoms, age at which onset occurs, effect on lifestyle—can vary considerably. However, it is most commonly observed as becoming manifest in patients between the ages of 30 and 50 years.

It was discovered in 1993 that Huntington's disease is caused by a single gene. A person with one parent who has the gene has a 50 percent chance of inheriting the faulty gene, and if that happens, it is certain that the disease will manifest itself during the lifetime of the patient, except in the case of an early death. Early possible symptoms include short—term memory lapse, behavior change, uncontrolled movement (mild), and clumsiness. As the disease develops, more severe involuntary movement takes place, as well as the loss of communication skills and other effects caused by these symptoms.

These symptoms, especially as they become more severe, can be very distressing, both for the patient and for carers and loved ones. The patient is likely to suffer additional psychological issues including depression and mood swings, which make care provision more trying. A range of medical assistance is likely to be required to deal with the secondary effects of the disease (e.g., psychological counselors, nutritionists, and occupational therapists) in addition to dealing with the root cause. In cases in which the presence of the gene in a family is not known, then it can take some time before the reason for the symptoms becomes clear. Where the presence of the gene is known in the family, then there is an effective test to determine whether it is present in an individual. Embryos are tested for the presence of the gene in some countries before use in in vitro fertilization treatments.