The decision to have such a test is a momentous one and should not be taken lightly. Most centers that do predictive testing, including ours, require a period of counseling before and after the test. Onset is usually in mid-life, but can occur any time from childhood to old age. The initial signs of this disorder may be subtle. HD is characterized by a movement disorder , dementia, and psychiatric disturbances.
Additional characteristics of HD include personality changes , weight loss probably from a combination of difficulty eating, and calories burned by the involuntary movements , difficulty swallowing, and hard-to-understand speech. Once an individual develops signs of HD the course of the disease can last anywhere from ten to thirty years. Typically, the course of HD can be roughly divided into three stages. Early Stage: In this stage patients can still perform most of their usual activities.
They may still be working and may still be able to drive. Involuntary movements are mild and infrequent, speech is still clear, and dementia, if present at all, is mild. 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. A longer repeat in the HTT gene may cause earlier onset of symptoms.
This phenomenon is called anticipation. Diagnosis Diagnosis. 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. 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. Treatment Treatment. 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.
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. Prognosis Prognosis. 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. Most people with HD survive for years after the onset of symptoms. The average age at death ranges from years, but the range may be broader.
In a large study, pneumonia and cardiovascular heart disease were the most common primary causes of death. 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. Find a Specialist Find a Specialist. Healthcare Resources To find a medical professional who specializes in genetics, you can ask your doctor for a referral or you can search for one yourself. You can also learn more about genetic consultations from MedlinePlus Genetics. Related Diseases Related Diseases.
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 Research. Clinical Research Resources ClinicalTrials. Click on the link to go to ClinicalTrials. Please note: Studies listed on the ClinicalTrials. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.
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.
Organizations Organizations. Organizations Supporting this Disease. Do you know of an organization? Living With Living With. In addition, some programs may provide financial assistance for additional expenses related to a patient's diagnosis such as travel to see a specialist.
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.
Department of Labor. Learn More Learn More. Where to Start MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
This website is maintained by the National Library of Medicine. 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. Click on the link to view information on this topic.
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. Defective huntingtin protein leads to brain changes that cause abnormal involuntary movements, a severe decline in thinking and reasoning skills, and irritability, depression and other mood changes. Symptoms of Huntington's disease usually develop between ages 30 and 50, but they can appear as early as age 2 or as late as The hallmark symptom of Huntington's disease is uncontrolled movement of the arms, legs, head, face and upper body.
Huntington's disease also causes a decline in thinking and reasoning skills, including memory, concentration, judgment, and ability to plan and organize. Huntington's disease brain changes lead to alterations in mood, especially depression, anxiety, and uncharacteristic anger and irritability. Another common symptom is obsessive-compulsive behavior, leading a person to repeat the same question or activity over and over.
Scientists identified the defective gene that causes Huntington's disease in A diagnostic genetic test is now available. The test can confirm that the defective gene for huntingtin protein is the cause of symptoms in people with suspected Huntington's disease and can detect the defective gene in people who don't yet have symptoms but are at risk because a parent has Huntington's.
Experts strongly recommend professional genetic counseling both before and after genetic testing for Huntington's disease. The huntingtin gene defect involves extra repeats of one specific chemical code in one small section of chromosome 4.
The normal huntingtin gene includes 17 to 20 repetitions of this code among its total of more than 3, codes. Figure 3. Figure 4. Figure 5: Restriction map of the G8 insert and the corresponding region of chromosome 4. Identifying the HD Gene. Discovering the HTT Mutation.
References and Recommended Reading Bates, G. Nature Reviews Genetics 6 , — link to article Gusella, J. Nature , — link to article Hoffman, J. Virchows Archiv A , — Huntington, G. On chorea. Medical and Surgery Reporter 26 , — MacDonald et al. Article History Close. Share Cancel. Revoke Cancel.
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