Huntington chorea; Huntington's disease DefinitionHuntington disease (HD) is a genetic disorder in which nerve cells in certain parts of the brain waste away, or degenerate. The disease is passed down through families. CausesHD is caused by a genetic defect on chromosome 4. The defect causes a part of your DNA to occur many more times than it is supposed to. This defect is called a CAG repeat. Normally, this section of DNA is repeated 10 to 28 times. But in people with HD, it is repeated 36 to 120 times. As the gene is passed down through families, the number of repeats tends to get larger. The larger the number of repeats, the higher a person's chance of developing symptoms at an earlier age. Therefore, as the disease is passed along in families, symptoms develop at younger and younger ages. There are two forms of HD:
If one of your parents has HD, you have a 50% chance of getting the gene. If you get the gene from your parents, you can pass it on to your children, who will also have a 50% chance of getting the gene. If you do not get the gene from your parents, you cannot pass the gene on to your children. SymptomsAbnormal behaviors may occur before movement problems develop, and can include:
Abnormal and unusual movements include:
Abnormal movements can lead to falls. Dementia that slowly gets worse, including:
Additional symptoms that may be associated with this disease include:
Symptoms in children:
Exams and TestsYour health care provider will perform a physical exam and may ask about your family history and symptoms. An exam of the nervous system will also be done. Other tests that may show signs of HD include: Genetic testing is available to determine whether a person carries the gene for HD. TreatmentThere is no cure for HD. There is no known way to stop the disease from getting worse. The goal of treatment is to slow the symptoms and help the person function for as long as possible. Medicines can be prescribed, depending on the symptoms.
Depression and suicide are common among persons with HD. People with HD are prone to behavioral problems including aggressive behavior. It is important for caregivers to monitor for symptoms and seek medical help for the person right away. Behavioral medicine specialists can help affected people cope. As the disease progresses, the person will need assistance and supervision, and may eventually need 24-hour care. Genetic counseling is very important for discussing prognosis and family planning. Support GroupsMore information and support for people with HD and their families can be found at:
Outlook (Prognosis)HD causes disability that gets worse over time. People with HD usually die within 15 to 20 years. The cause of death is often infection. Suicide is also common. It is important to realize that HD affects people differently. The number of CAG repeats may determine the severity of symptoms. People with few repeats may have mild abnormal movements later in life and slow disease progression. Those with a large number of repeats may be severely affected at a young age. When to Contact a Medical ProfessionalCall your provider if you or a family member develops symptoms of HD. If you or someone you know is thinking about suicide, call or text 988 or chat 988lifeline.org. You can also call 1-800-273-8255 (1-800-273-TALK). The 988 Suicide and Crisis Lifeline provides free and confidential support 24/7, anytime day or night. You can also call 911 or the local emergency number or go to the hospital emergency room. DO NOT delay. If someone you know has attempted suicide, call 911 or the local emergency number right away. DO NOT leave the person alone, even after you have called for help. PreventionGenetic counseling is advised if there is a family history of HD. Experts also recommend genetic counseling for couples with a family history of this disease who are considering having children. ReferencesCaron NS, Wright GEB, Hayden MR. Huntington disease. In: Adam MP, Ardinger HH, Pagon RA, et al, eds. GeneReviews. Seattle, WA: University of Washington. www.ncbi.nlm.nih.gov/books/NBK1305/. Updated June 11, 2020. Accessed August 12, 2023. Jankovic J, Lang AE. Diagnosis and assessment of Parkinson disease and other movement disorders. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley's and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 24. | ||
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Review Date: 4/29/2023 Reviewed By: Joseph V. Campellone, MD, Department of Neurology, Cooper Medical School of Rowan University, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team. View References The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. No warranty of any kind, either expressed or implied, is made as to the accuracy, reliability, timeliness, or correctness of any translations made by a third-party service of the information provided herein into any other language. © 1997- A.D.A.M., a business unit of Ebix, Inc. Any duplication or distribution of the information contained herein is strictly prohibited. | ||
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