Huntington's disease (HD), also known as Huntington's chorea, is an inherited disorder that results in death of brain cells. The earliest symptoms are often subtle. Huntington's disease causes a progressive breakdown of nerve cells in the brain. Find out about symptoms, diagnosis and treatment. 6 days ago Huntington disease is a progressive brain disorder that causes uncontrolled movements, emotional problems, and loss of thinking ability.
However, most people do these from time to time. As HD progresses, the uncontrollable movements occur more often and with usually with more intensity.
Eventually they may become slower as the muscles become more rigid. Eventually, the person will no longer be able to walk or talk, and they will need full nursing care. However, they will usually understand most of what is being said and will be aware of friends and family members.
Weight loss can make the symptoms worse and weaken the patient's immune system, making them more vulnerable to infections and other complications.
HD itself is not usually fatal, but choking, pneumonia or another infection can be. Throughout all stages, it is important to adjust the patient's diet to ensure adequate food intake. HD is caused by a faulty gene mhTT on chromosome number 4. A normal copy of the gene produces huntingtin, a protein. The faulty gene is larger than it should be. If it repeats 40 times or more, symptoms are likely.
This change results in a larger form of huntingtin. This is toxic, and, as it accumulates in the brain, it causes damage to brain cells. Some brain cells are sensitive to the larger form of huntingtin, especially those related to movement, thinking, and memory.
It undermines their function and eventually destroys them. Scientists are not sure exactly how this happens. HD is known as an autosomal dominant disorder. This means that only one copy of the faulty gene, inherited from either the mother or the father, is necessary to produce the disease. A person with the gene has one good copy of the gene and one faulty copy of the gene. Any offspring will inherit either the good copy or the faulty one.
The child who inherits the good copy will not develop HD. The child who inherits a faulty copy will. Each child has a 50 percent chance of inheriting the faulty gene. If they inherit the faulty gene, each of their children will have a 50 percent chance of inheriting it.
HD can affect several generations. A person who does not inherit the faulty gene will not develop HD and cannot pass it on to their children. A child who inherits the faulty gene will develop HD if they reach the age when symptoms are due to emerge. Around 10 percent of cases of HD start before the age of 20 years. Between 30 and 50 percent of people with JHD have seizures. HD is currently incurable.
There is no treatment that can reverse its progression or slow it down. Side effects include depression and suicidal thoughts or actions. Anyone who has a diagnosis of depression, especially with suicidal thoughts, should not use tretrabenazine.
For depression and some obsessive-compulsive features that can appear with HD, the doctor may prescribe:. Speech therapy can help patients find ways to express words and phrases and communicate in a more effective way. A physical therapist can help improve muscle strength and flexibility, leading to better balance and a reduced the risk of falling.
An occupational therapist can help the patient develop strategies for coping with concentration and memory problems, as well as making the home safer. The doctor will examine the patient and ask about family and medical history, and symptoms, such as recent emotional changes.
Imaging tests, such as a CT or MRI scan , are sometimes used to identify changes in the patient's brain structure, and to rule out other disorders. HD has a major emotional, mental, social, and economic impact on the lives of the individual and their families.
After diagnosis, a person will normally live for 15 to 20 years , but the duration ranges from 10 to 30 years. A person with JHD will probably live around 10 years. This form progresses more quickly. Additionally, an increasing number of people with Huntington's disease are turning to palliative care, which aims to improve quality of life through the treatment of the symptoms and stress of serious illness, in addition to their other treatments. Tetrabenazine was approved in for treatment of chorea in Huntington's disease in the EU, and in in the US.
Psychiatric symptoms can be treated with medications similar to those used in the general population. The families of individuals, and society at large, who have inherited or are at risk of inheriting HD have generations of experience of HD, but may be unaware of recent breakthroughs in understanding the disease, and of the availability of genetic testing.
Genetic counseling benefits these individuals by updating their knowledge, seeking to dispel any unfounded beliefs that they may have, and helping them consider their future options and plans. Also covered is information concerning family planning choices, care management, and other considerations.
A longer repeat results in an earlier age of onset and a faster progression of symptoms. The largest risk is pneumonia , which causes death in one third of those with HD.
As the ability to synchronize movements deteriorates, difficulty clearing the lungs and an increased risk of aspirating food or drink both increase the risk of contracting pneumonia. The second greatest risk is heart disease , which causes almost a quarter of fatalities of those with HD. It is unclear to what extent suicidal thoughts are influenced by behavioral symptoms, as they signify sufferers' desires to avoid the later stages of the disease.
The late onset of Huntington's disease means it does not usually affect reproduction. The rate of occurrence is highest in peoples of Western European descent, averaging around 7 per , people, and is lower in the rest of the world; e.
A epidemiological study of the prevalence of Huntington's disease in the UK between and found that the average prevalence for the UK was Until the discovery of a genetic test , statistics could only include clinical diagnosis based on physical symptoms and a family history of HD, excluding those who died of other causes before diagnosis.
These cases can now be included in statistics; and, as the test becomes more widely available, estimates of the prevalence and incidence of the disorder are likely to increase. Although Huntington's has been recognized as a disorder since at least the Middle Ages , the cause has been unknown until fairly recently. Huntington's was given different names throughout this history as understanding of the disease changed.
Originally called simply 'chorea' for the jerky dancelike movements associated with the disease, HD has also been called "hereditary chorea" and "chronic progressive chorea". Waters described "a form of chorea, vulgarly called magrums", including accurate descriptions of the chorea, its progression, and the strong heredity of the disease. The first thorough description of the disease was by George Huntington in Examining the combined medical history of several generations of a family exhibiting similar symptoms, he realized their conditions must be linked; he presented his detailed and accurate definition of the disease as his first paper.
Huntington described the exact pattern of inheritance of autosomal dominant disease years before the rediscovery by scientists of Mendelian inheritance. When either or both the parents have shown manifestations of the disease But if by any chance these children go through life without it, the thread is broken and the grandchildren and great-grandchildren of the original shakers may rest assured that they are free from the disease.
Sir William Osler was interested in the disorder and chorea in general, and was impressed with Huntington's paper, stating that "In the history of medicine, there are few instances in which a disease has been more accurately, more graphically or more briefly described. During the rediscovery of Mendelian inheritance at the turn of the 20th century, HD was used tentatively as an example of autosomal dominant inheritance. Researchers have found contrary evidence; for instance, the community of the family studied by George Huntington openly accommodated those who exhibited symptoms of HD.
The search for the cause of this condition was enhanced considerably in , when the Hereditary Disease Foundation HDF was created by Milton Wexler , a psychoanalyst based in Los Angeles , California , whose wife Leonore Sabin had been diagnosed earlier that year with Huntington's disease.
The foundation was involved in the recruitment of over scientists in the Huntington's Disease Collaborative Research Project who over a year period worked to locate the responsible gene.
Thanks to the HDF, the ongoing US-Venezuela Huntington's Disease Collaborative Research Project was started in , and reported a major breakthrough in with the discovery of the approximate location of a causal gene. It involved over 18, people—mostly from a single extended family. Among other innovations, the project developed DNA -marking methods which were an important step in making the Human Genome Project possible.
In the same time frame, key discoveries concerning the mechanisms of the disorder were being made, including the findings by Anita Harding 's research group on the effects of the gene's length. Modelling the disease in various types of animals, such as the transgenic mouse developed in , enabled larger scale experiments. As these animals have faster metabolisms and much shorter lifespans than humans, results from experiments are received sooner, speeding research.
The discovery that mHTT fragments misfold led to the discovery of the nuclear inclusions they cause. These advances have led to increasingly extensive research into the proteins involved with the disease, potential drug treatments, care methods, and the gene itself.
The condition was formerly called 'Huntington's chorea' but this term has been replaced by 'Huntington's disease' because not all patients develop chorea and due to the importance of cognitive and behavioral problems. Huntington's disease, particularly the application of the genetic test for the disease, has raised several ethical issues. The issues for genetic testing include defining how mature an individual should be before being considered eligible for testing, ensuring the confidentiality of results, and whether companies should be allowed to use test results for decisions on employment, life insurance or other financial matters.
There was controversy when Charles Davenport proposed in that compulsory sterilization and immigration control be used for people with certain diseases, including HD, as part of the eugenics movement.
Some HD research has ethical issues due to its use of animal testing and embryonic stem cells. The development of an accurate diagnostic test for Huntington's disease has caused social, legal, and ethical concerns over access to and use of a person's results. There is consensus for testing only individuals who are considered cognitively mature, although there is a counter-argument that parents have a right to make the decision on their child's behalf.
With the lack of an effective treatment, testing a person under legal age who is not judged to be competent is considered unethical in most cases.
There are ethical concerns related to prenatal genetic testing or preimplantation genetic diagnosis to ensure a child is not born with a given disease. This would require parts of the process to be kept secret from the parent. In , after experiencing HD in his wife's family, Dr.
Milton Wexler was inspired to start the Hereditary Disease Foundation HDF , with the aim of curing genetic illnesses by coordinating and supporting research. Since then, support and research organizations have formed in many countries around the world and have helped to increase public awareness of HD.
A number of these collaborate in umbrella organizations, like the International Huntington Association and the European HD network. The largest funder of Huntington's disease research globally, in terms of financial expenditure,  is the CHDI Foundation , a US non-profit biomedical foundation that aims to "rapidly discover and develop drugs that delay or slow Huntington's disease". Research into the mechanism of HD has focused on identifying the functioning of HTT, how mHTT differs or interferes with it, and the brain pathology that the disease produces.
Research is conducted using in vitro methods, animal models and human volunteers. Animal models are critical for understanding the fundamental mechanisms causing the disease and for supporting the early stages of drug development.
Research is being conducted on many different approaches to prevent Huntington's disease or slow its progression.
Disease-modifying strategies can be broadly grouped into three categories: In addition, novel therapies to improve brain functioning are under development; these seek to produce symptomatic rather than disease-modifying therapies, and include phosphodiesterase inhibitors.
Gene silencing aims to reduce the production of the mutant protein, since HD is caused by a single dominant gene encoding a toxic protein. Gene silencing experiments in mouse models have shown that when the expression of mHTT is reduced, symptoms improve.
One way of accomplishing this is to identify polymorphisms present on only one allele and produce gene silencing drugs that target polymorphisms in only the mutant allele. Among the approaches aimed at improving cell survival in the presence of mutant huntingtin are correction of transcriptional regulation using histone deacetylase inhibitors , modulating aggregation of huntingtin, improving metabolism and mitochondrial function and restoring function of synapses. Stem cell therapy is the replacement of damaged neurons by transplantation of stem cells into affected regions of the brain.
Experiments have yielded mixed results using this technique in animal models and preliminary human clinical trials.
Several clinical trials of new experimental treatments are underway and planned in Huntington's disease. Compounds that have failed to prevent or slow progression of Huntington's disease in human trials include remacemide , coenzyme Q10 , riluzole , creatine , minocycline , ethyl-EPA , phenylbutyrate and dimebon. From Wikipedia, the free encyclopedia. List of Huntington's disease media depictions. Archived from the original on 27 July Retrieved 19 July A Journey through History".
Tremor and Other Hyperkinetic Movements. Archived from the original on 4 July Archived from the original on 19 November Retrieved 18 November Huntington's Disease Society of America. Archived from the original on 9 April Retrieved 17 March The Journal of Neuropsychiatry and Clinical Neurosciences. Archived from the original on 10 February Retrieved 12 March Huntington's Outreach Project for Education, at Stanford.
Archived from the original on 8 August Retrieved 4 August Huntington's Disease — Third Edition. Neurology, Psychiatry and Brain Research 8: Archived from the original PDF on 23 March Retrieved 17 September HD Society of Canada. Archived from the original PDF on 25 June Retrieved 10 August Bradley's neurology in clinical practice 6th ed. Archived from the original on 9 July Color Atlas of Genetics 2nd ed. Journal of Medical Genetics. Archived from the original on 14 July Journal of Huntington's Disease.
Trends in Biochemical Sciences. Expert Reviews in Molecular Medicine. American Journal of Human Genetics. Histone modifications in Huntington's disease". Archived from the original on 26 November From Molecular Mechanisms to Clinical Applications". Oxidative Medicine and Cellular Longevity. Archived from the original on 18 February The longer the CAG repeat, the earlier the onset of disease. In cases of JHD, the repeat often exceeds Diagnosis is based on clinical symptoms and signs in an individual with a parent with proven HD and is confirmed by DNA determination Premanifest diagnosis should only be performed by multidisciplinary teams in healthy at-risk adult individuals who want to know whether they carry the mutation or not.
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. Prenatal diagnosis is possible by chorionic villus sampling or amniocentesis. Pre-implantation diagnosis with in vitro fertilization is offered in several countries.
To date, no cure is available. Management should be multidisciplinary and is based on treating symptoms with a view to improving quality of life. Chorea is treated with dopamine receptor blocking or depleting agents. Medication and non-medical care for depression and aggressive behavior may be required. The progression of the disease leads to complete dependency in daily life, which results in patients requiring full-time care, and finally death.
The most common cause of death is pneumonia, followed by suicide. Other search option s Alphabetical list. Summary and related texts. Check this box if you wish to receive a copy of your message.
What you need to know about Huntington's disease
Huntington's disease – learn about HD symptoms, diagnosis, causes and treatments and how this disorder relates to Alzheimer's and other dementias. Clinical presentation of juvenile Huntington disease. Apresentação clínica da forma juvenil da doença de Huntington. Heloísa H. RuoccoI; Iscia Lopes-Cendes II;. Huntington's disease (HD) is a fatal genetic disorder, which causes the progressive breakdown of neurons in the human brain. HD deteriorates human physical.