Rare Endocrinology News

Disease Profile


Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.

1-9 / 1 000 000

US Estimated

Europe Estimated

Age of onset





Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.

Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

DYT1; Early onset torsion dystonia; EOTD;


Congenital and Genetic Diseases; Nervous System Diseases


Early-onset generalized dystonia is a neurologic movement disorder that usually begins in childhood or adolescence. This is the most common hereditary form of dystonia.[1] Symptoms start in one part of the body (usually an arm, foot, or leg) and are usually first apparent with actions such as writing or walking. With time, the contractions may spread to other parts of the body, causing the muscles to twist the body into unnatural positions.[1][2][3] Symptoms can vary greatly, even among members of the same family. For some, the disorder can cause significant disability, while others may experiences only isolated writer’s cramp.[1][3] A small deletion in the DYT1 gene is the major cause of early-onset dystonia.[2][3] The genetic change responsible for early onset generalized dystonia is inherited in an autosomal dominant manner, though not everyone who inherits the genetic change will develop the condition. It is thought that only 30% of individuals who inherit the mutation will develop DYT1 dystonia. This is known as reduced penetrance .[2][3] Treatments include oral medications such as trihexyphenidyl, baclofen, and clonazepam. Botulinum toxin injections may be used in conjunction with oral medications when symptoms are focused in a certain area. In some cases, deep brain stimulation may be indicated.[3]


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.

Medical Terms Other Names
Learn More:
80%-99% of people have these symptoms
Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait

[ more ]

30%-79% of people have these symptoms
Abnormality of the voice
Voice abnormality
1%-4% of people have these symptoms
Incomplete penetrance
Percent of people who have these symptoms is not available through HPO
Abnormal posturing
Autosomal dominant inheritance
Eyelid spasm
Eyelid twitching
Involuntary closure of eyelid
Spontaneous closure of eyelid

[ more ]

Difficulty articulating speech
Generalized hypotonia
Decreased muscle tone
Low muscle tone

[ more ]

Prominent swayback
Hunched back
Round back

[ more ]

Muscular hypotonia
Low or weak muscle tone
Torsion dystonia
Wry neck
Writer's cramp


Making a diagnosis for a genetic or rare disease can often be challenging. Healthcare professionals typically look at a person’s medical history, symptoms, physical exam, and laboratory test results in order to make a diagnosis. The following resources provide information relating to diagnosis and testing for this condition. If you have questions about getting a diagnosis, you should contact a healthcare professional.

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.


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.

Learn more

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

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 DYT-TOR1A. Click on the link to view a sample search on this topic.


  1. Frucht, Steven. Dystonia. National Organization of Rare Disorders (NORD). 2015; https://rarediseases.org/rare-diseases/dystonia/. Accessed 10/31/2016.
  2. DYSTONIA 1, TORSION, AUTOSOMAL DOMINANT; DYT1. Online Mendelian Inheritance in Man (OMIM). August 9, 2016; https://www.omim.org/entry/128100. Accessed 10/31/2016.
  3. Ozelius, Laurie and Lubarr, Naomi.. DYT1 Early-Onset Primary Dystonia. GeneReviews. January 2, 2014; https://www.ncbi.nlm.nih.gov/books/NBK1492/. Accessed 10/31/2016.