National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Huntington disease

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Other Names:
Huntington's chorea; Huntington's disease; HD
Categories:
Huntington disease (HD) is an inherited condition that causes progressive degeneration of neurons in the brain. Signs and symptoms usually develop between ages 35 to 44 years and may include uncontrolled movements, loss of intellectual abilities, and various emotional and psychiatric problems. People with HD usually live for about 15 to 20 years after the condition begins. It is caused by changes (mutations) in the HTT gene and is inherited in an autosomal dominant manner. Treatment is based on the symptoms present in each person and may include various medications.[1][2]

There is also a less common, early-onset form of HD which begins in childhood or adolescence. For more information on this form, please visit GARD's juvenile Huntington disease Web page.
Last updated: 7/8/2015
Huntington disease (HD) is a progressive disorder that causes motor, cognitive, and psychiatric signs and symptoms. On average, most people begin developing features of HD between ages 35 and 44. Signs and symptoms vary by stage and may include:[2][3]

Early stage:
  • Behavioral disturbances
  • Clumsiness
  • Moodiness
  • Irritability
  • Paranoia
  • Apathy
  • Anxiety
  • Hallucinations
  • Abnormal eye movements
  • Depression
  • Impaired ability to detect odors
Middle stage:
  • Dystonia
  • Involuntary movements
  • Trouble with balance and walking
  • Chorea with twisting and writhing motions
  • Unsteady gait (style of walking)
  • Slow reaction time
  • General weakness
  • Weight loss
  • Speech difficulties
  • Stubbornness
Late stage:
  • Rigidity (continual tension of the muscles)
  • Bradykinesia (difficulty initiating and continuing movements)
  • Severe chorea
  • Serious weight loss
  • Inability to speak
  • Inability to walk
  • Swallowing problems
  • Inability to care for oneself
There is also a less common, early-onset form of HD which begins in childhood or adolescence. For more information on this form, please visit GARD's juvenile Huntington disease Web page.
Last updated: 7/7/2015

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Showing of 21 |
Medical Terms Other Names
Learn More:
HPO ID
30%-79% of people have these symptoms
Abnormality of movement
Movement disorder
Unusual movement
[ more ] 		0100022
Abnormality of the voice
Voice abnormality
0001608
Behavioral abnormality
Behavioral changes
Behavioral disorders
Behavioral disturbances
Behavioral problems
Behavioral/psychiatric abnormalities
Behavioural/Psychiatric abnormality
Psychiatric disorders
Psychiatric disturbances
[ more ] 		0000708
Cerebral cortical atrophy
Decrease in size of the outer layer of the brain due to loss of brain cells
0002120
Dementia
Dementia, progressive
Progressive dementia
[ more ] 		0000726
Developmental regression
Loss of developmental milestones
Mental deterioration in childhood
[ more ] 		0002376
EEG abnormality 0002353
Spasticity
Involuntary muscle stiffness, contraction, or spasm
0001257
5%-29% of people have these symptoms
Rigidity
Muscle rigidity
0002063
Percent of people who have these symptoms is not available through HPO
Abnormality of eye movement
Abnormal eye movement
Abnormal eye movements
Eye movement abnormalities
Eye movement issue
[ more ] 		0000496
Autosomal dominant inheritance 0000006
Bradykinesia
Slow movements
Slowness of movements
[ more ] 		0002067
Cerebellar atrophy
Degeneration of cerebellum
0001272
Chorea 0002072
Depressivity
Depression
0000716
Gait ataxia
Inability to coordinate movements when walking
0002066
Gliosis 0002171
Hyperreflexia
Increased reflexes
0001347
Neuronal loss in central nervous system
Loss of brain cells
0002529
Personality changes
Personality change
0000751
Seizure 0001250
Showing of 21 |
Last updated: 7/1/2020
Huntington disease (HD) is caused by a change (mutation) in the HTT gene. This gene gives instructions for making a protein called huntingtin. The exact function of this protein is unclear, but it appears to be important to nerve cells (neurons) in the brain.[1]

The HTT gene mutation that causes HD involves a DNA segment known as a CAG trinucleotide repeat. This segment is made up of three DNA building blocks that repeat multiple times in a row. The CAG segment in a normal HTT gene repeats about 10 to 35 times. In people with HD, it may repeat from 36 to over 120 times. People with 36 to 39 CAG repeats (an intermediate size) may or may not develop HD, while people with 40 or more repeats almost always develop HD.[1]
Last updated: 7/8/2015
Huntington disease (HD) is inherited in an autosomal dominant manner.[2] This means that having a change (mutation) in only one of the 2 copies of the HTT gene is enough to cause the condition. When a person with HD has children, each child has a 50% (1 in 2) chance to inherit the mutated gene and develop the condition.

Most people with HD have an affected parent. The family history can sometimes appear negative for various reasons even though a parent carries, or carried, a mutation in the HTT gene. In rare cases, HD is caused by a new (de novo) mutation in the HTT gene, in which case the disease occurs for the first time in the affected person and is not inherited from a parent.[2]

As HD is passed through generations, the size of the mutation in the HTT gene (called a trinucleotide repeat) often increases. A longer repeat in the HTT gene may cause earlier onset of symptoms. This phenomenon is called anticipation.[1]
Last updated: 10/21/2015
A diagnosis of Huntington disease is typically suspected in people with characteristic signs and symptoms of the condition and a family history consistent with autosomal dominant inheritance. The diagnosis can then be confirmed with genetic testing that identifies a specific type of change (mutation) in the HTT gene.[2]
Last updated: 7/8/2015

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.
  • The Division of Neurogenetics at the University of Washington is a tertiary specialty that provides clinical services to adults in the general public as well as training. They have created a booklet entitled, "Huntington Disease: Making an Informed Choice,  that can be downloaded at no charge.
  • Orphanet lists international laboratories offering diagnostic testing for this condition.
Unfortunately, there is currently no cure for Huntington disease (HD). The current goal of treatment is to slow down the course of the disease and help affected people function for as long and as comfortably as possible.[3]

Current treatment strategies involve the use of various medications to treat specific symptoms such as abnormal movements and behaviors. Depression and suicide are more common among affected people, so caregivers should monitor for associated symptoms and seek help if necessary. As symptoms of the disease worsen, affected people need more assistance, supervision, and care.[3]
Last updated: 7/8/2015

FDA-Approved Treatments

The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.

Huntington disease (HD) is progressive, eventually leading to disability and death (usually from a coexisting illness or infection). However, the disease affects everyone differently; the age of onset, specific symptoms, and rate of progression varies for each person with HD.

While the symptoms of HD are well-characterized, their progression (especially in the early and middle stages) remains unpredictable. With the approach of late-stage HD, affected people have speech difficulty and weight loss. In the late stage, affected people lose bowel and bladder control.[4]

The duration of the disease (from onset until death) varies considerably, with an average of approximately 19 years. Most people with HD survive for 10-25 years after the onset of symptoms. The average age at death ranges from 51-57 years, but the range may be broader. In a large study, pneumonia and cardiovascular (heart) disease were the most common primary causes of death.[5]

The length of the CAG repeat (the type of mutation in the HTT gene responsible for HD) is the most important factor that determines age of onset of HD. However, there is still a lot of variability. Both genetic and environmental factors are thought to play a role on the age of onset in people with a mutation. Inheritance through the father can lead to more repeat expansion and earlier onset through succeeding generations, a phenomenon called anticipation.[5]

People with HD, family members, and/or caregivers with specific questions about prognosis should speak with their health care provider.
Last updated: 10/21/2015

If you need medical advice, you can look for doctors or other healthcare professionals who have experience with this disease. You may find these specialists through advocacy organizations, clinical trials, or articles published in medical journals. You may also want to contact a university or tertiary medical center in your area, because these centers tend to see more complex cases and have the latest technology and treatments.

If you can’t find a specialist in your local area, try contacting national or international specialists. They may be able to refer you to someone they know through conferences or research efforts. Some specialists may be willing to consult with you or your local doctors over the phone or by email if you can't travel to them for care.

You can find more tips in our guide, How to Find a Disease Specialist. We also encourage you to explore the rest of this page to find resources that can help you find specialists.

Healthcare Resources

Related diseases are conditions that have similar signs and symptoms. A health care provider may consider these conditions in the table below when making a diagnosis. Please note that the table may not include all the possible conditions related to this disease.

Conditions with similar signs and symptoms from Orphanet
Differential diagnoses include other causes of chorea including general internal disorders or iatrogenic disorders. Phenocopies (clinically diagnosed cases of HD without the genetic mutation) are observed.
Visit the Orphanet disease page for more information.

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Huntington disease. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Patient Registry

  • The National Research Roster for Huntington Disease Patients and Families (hdRoster) was established in 1979 at Indiana University. Funded by the National Institute of Neurological Disorders and Stroke, a branch of the National Institutes of Health, the Roster computerizes the names of families, including information about the history of HD in the family (family trees) and other related data. This information identifies HD patients and families who are interested in participating in research projects.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Organizations Supporting this Disease

Social Networking Websites

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Financial Resources

  • National Organization for Rare Disorders (NORD) has Disease-Specific Assistance Programs designed to help patients with out-of-pocket costs such as monthly insurance premiums or deductibles. In addition, some programs may provide financial assistance for additional expenses related to a patient's diagnosis such as travel to see a specialist.
  • The Social Security Administration has included this condition in their Compassionate Allowances Initiative. This initiative speeds up the processing of disability claims for applicants with certain medical conditions that cause severe disability. More information about Compassionate Allowances and applying for Social Security disability is available online.

Community Resources

  • The Job Accommodation Network (JAN) has information on workplace accommodations and disability employment issues related to this condition. JAN is a service of the Office of Disability Employment Policy in the U.S. Department of Labor.

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • Genetics Home Reference (GHR) contains information on Huntington disease. This website is maintained by the National Library of Medicine.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The National Human Genome Research Institute's (NHGRI) website has an information page on this topic. NHGRI is part of the National Institutes of Health and supports research on the structure and function of the human genome and its role in health and disease.
  • The National Institute of Neurological Disorders and Stroke (NINDS) collects and disseminates research information related to neurological disorders. Click on the link to view information on this topic.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

  • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Huntington disease. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know. Submit a new question

  • My father has Huntington chorea and his body is stiffening up. I would like to know if this means he is going to pass away soon. His side of the family has had this disease. It has not skipped anyone yet. I was young and don't remember what happens. See answer

  • Resent test results showed 17 repeats from each parent. The social worker suggested that the test might be in error because the number of repeats is the same. Instead of telling the person they did not have HD, she suggested the test was in error. How likely or unlikely is it for the number of repeats to be the same? When one needs a definitive positive or negative, this negative result, being suggested as possibly an error, is heart wrenching, especially for the patient and her family. Is it uncommon for the numbers to be the same? Should she be retested? How common are mistakes in diagnosing HD? The patient lost a parent to HD. See answer

  • Can a person of any gender, age, or ethnicity have Huntington disease? See answer

  • I am a personal trainer working with a client who has HD.  While I have seen progress with the exercises we are doing, I am looking for more information regarding the types of exercises that are found to be most effective or certain exercises that should be avoided. See answer

  • What tests will my doctor order to confirm if I have Huntington disease? See answer

  • A friend of mine has been diagnosed with Huntington disease. No one else in his family has this condition. Is it possible that a chemical exposure could have caused it, such as to vinyl chloride? See answer

  • I have a family history of Huntington's disease.  My mother was diagnosed with it about 5 years ago.  I just needed to know some information about where I can get tested.  Also, how early can they start treatment if I am diagnosed with it?  I'm only 21 years old.  I just thought that maybe the sooner they start the better. See answer


  1. Huntington disease. Genetics Home Reference. June, 2013; http://ghr.nlm.nih.gov/condition/huntington-disease.
  2. Simon C Warby, Rona K Graham, and Michael R Hayden. Huntington Disease. GeneReviews. December 11, 2014; http://www.ncbi.nlm.nih.gov/books/NBK1305/.
  3. Huntington disease. MedlinePlus. May 28, 2013; http://www.nlm.nih.gov/medlineplus/ency/article/000770.htm.
  4. Idan Sharon. Huntington Disease Dementia. Medscape Reference. April 18, 2014; http://emedicine.medscape.com/article/289706-overview.
  5. Fredy J Revilla. Huntington Disease. Medscape Reference. July 9, 2015; http://emedicine.medscape.com/article/1150165-overview.