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Disease Profile

Dopa-responsive dystonia

Prevalence
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

331 - 2,979

US Estimated

1-9 / 1 000 000

514 - 4,622

Europe Estimated

Age of onset

Childhood

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ICD-10

G24.1

Inheritance

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

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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

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X-linked
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.

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

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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.

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Not applicable

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Other names (AKA)

HPD with diurnal fluctuation; Hereditary progressive dystonia with diurnal fluctuation; DYT-GCH1 (subtype);

Categories

Congenital and Genetic Diseases; Metabolic disorders; Nervous System Diseases

Summary

Dopa-responsive dystonia (DRD) is an inherited type of dystonia that typically begins during childhood but may begin in adolescence or adulthood.[1] Depending on the specific type of DRD, specific symptoms can vary. Features can range from mild to severe. In most cases, dystonia begins in the lower limbs and spreads to the upper limbs over time. Symptoms may include unusual limb positioning; a lack of coordination when walking or running; sleep problems; and episodes of depression. Affected people also often develop a group of movement abnormalities called parkinsonism. Although movement difficulties usually worsen with age, they often stabilize around age 30. DRD may be caused by mutations in the GCH1, TH or SPR genes, or the cause may be unknown. Depending on the genetic cause, DRD may be inherited in an autosomal dominant (most commonly) or autosomal recessive manner. This form of dystonia is called 'dopa-responsive' dystonia because the symptoms typically improve during treatment with levodopa and carbidopa.[2]

Symptoms

The most common form of dopa-responsive dystonia (DRD) is autosomal dominant DRD (caused by a mutation in the GCH1 gene). This form of DRD is usually characterized by childhood-onset dystonia that may be associated with parkinsonism at an older age. The average age of onset is 6 years, and females are 2-4 times more likely than males to be affected. Symptoms usually begin with lower limb dystonia, resulting in gait problems that can cause stumbling and falling. Symptoms are often worse later in the day, a phenomenon known as diurnal fluctuation. In rare cases, the first symptom may be arm dystonia, tremor of the hands, slowness of movements, or cervical dystonia. This form of DRD usually progresses to affect the whole body, and some people also develop parkinsonism. Depression, anxiety, sleep disturbances and obsessive-compulsive disorder have been reported in some people. Intellectual function is normal. Those with onset at older ages tend to be more mildly affected.[3]

Another form of DRD is due to a rare condition called sepiapterin reductase deficiency, which is inherited in an autosomal recessive manner. This form of DRD is also characterized by dystonia with diurnal fluctuations, but also affects motor and cognitive development. Onset usually occurs before the first year of life. Sleep disturbances and psychological symptoms (anxiety, irritability) are common later in childhood.[4]

A third form of DRD is autosomal recessive DRD, also called tyrosine hydroxylase deficiency. This form is characterized by a spectrum of symptoms, ranging from those seen in the autosomal dominant form to progressive infantile encephalopathy. Onset is usually in infancy. Intellectual disability, developmental motor delay, and various other features may be present.[5]

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:
HPO ID
80%-99% of people have these symptoms
Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait

[ more ]

0001288
Spasticity
Involuntary muscle stiffness, contraction, or spasm
0001257

Diagnosis

Dopa-responsive dystonia (DRD) is diagnosed based on the signs and symptoms present, results of laboratory tests (sometimes including genetic testing), and response to therapy with levodopa.

If DRD is suspected, a therapeutic trial with low doses of levodopa remains the most practical approach to the diagnosis. It is generally agreed that people with childhood-onset dystonia of unknown cause should be treated initially with levodopa. The characteristic symptoms and response to treatment are sufficient to establish the diagnosis for people with the most common form, autosomal dominant DRD. There is only one gene in which mutations are known to cause this form of DRD, but not all people with the disorder are found to have a mutation in the responsible gene. While finding a mutation may provide information about prognosis, it does not alter the treatment. Other types of laboratory tests, such as measuring specific substances or enzymes in the blood or cerebrospinal fluid (CSF), may be useful to support the diagnosis.[6]

For tyrosine hydroxylase deficiency, an autosomal recessive genetic cause of DRD, molecular genetic testing has confirmed the presence of mutations in all affected people to date. Specific laboratory tests performed on CSF help support the diagnosis but are not diagnostic on their own.[7]

For sepiapterin reductase deficiency, a very rare autosomal recessive form of DRD, there are distinctive findings in CSF and reduced or absent activity of sepiapterin reductase in fibroblasts. Molecular genetic testing can identify mutations in the responsible gene and confirm the diagnosis of this form of DRD.[4]

The major conditions that may have a similar presentation to DRD and are part of the differential diagnosis include early-onset parkinsonism, early-onset primary dystonia, and cerebral palsy or spastic paraplegia.[6]

People with specific questions about being evaluated for any form of dystonia should speak with a neurologist or other health care provider.

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.

    Organizations

    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

      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

      • Genetics Home Reference (GHR) contains information on Dopa-responsive dystonia. This website is maintained by the National Library of Medicine.

        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.
        • 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 Dopa-responsive dystonia. Click on the link to view a sample search on this topic.

          References

          1. Nirjal K Nikhar. Dopamine-Responsive Dystonia. Medscape. October 16, 2014; https://emedicine.medscape.com/article/1181084-overview.
          2. Dopa-responsive dystonia. Genetics Home Reference. May, 2012; https://ghr.nlm.nih.gov/condition/dopa-responsive-dystonia.
          3. Christoph Kamm. Dopa-responsive dystonia. Orphanet. November, 2013; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=255.
          4. Christoph Kamm. Dopa-responsive dystonia due to sepiapterin reductase deficiency. Orphanet. November, 2013; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=70594.
          5. Christoph Kamm. Autosomal recessive dopa responsive dystonia. Orphanet. November, 2013; https://www.orpha.net/consor/cgi-bin/OC_Exp.php?lng=en&Expert=101150.
          6. Yoshiaki Furukawa. GTP Cyclohydrolase 1-Deficient Dopa-Responsive Dystonia. GeneReviews. March 5, 2015; https://www.ncbi.nlm.nih.gov/books/NBK1508/.
          7. Yoshiaki Furukawa. Tyrosine Hydroxylase Deficiency. GeneReviews. July 17, 2014; https://www.ncbi.nlm.nih.gov/books/NBK1437/.

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