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Disease Profile

GNAO1 encephalopathy

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.

Unknown

Age of onset

#N/A

ICD-10

#N/A

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.

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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)

Early infantile epileptic encephalopathy-17

Summary

GNAO1 encephalopathy is a rare neurologic disorder that causes developmental delay, early infantile seizures, and abnormal movements. Specific symptoms may include seizures that start early in childhood, severe intellectual disability, poor muscle tone (hypotonia), irregular muscle contractions (chorea), and involuntary movements of the face and tongue (dyskinesia).[1][2] The severity of symptoms can vary. Symptoms may be triggered by strong emotions, illness, and purposeful movements.[2] GNAO1 encephalopathy is caused by mutations in the GNAO1 gene and inheritance is autosomal dominant.[3][4] Treatment aims to relieve individual symptoms and may not be effective for all people. In some cases, movement disorders have improved after the placement of a deep brain stimulator (DBS) device. Some have had improvement of seizures with anti-seizure medications or with a ketogenic diet, but others have not. While the long-term outcome has not been well-studied, the disease is typically very severe, with some people losing their motor skills in the early stages of the disease.[1]

Symptoms

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
5%-29% of people have these symptoms
Athetosis
Involuntary writhing movements in fingers, hands, toes, and feet
0002305
Chorea
0002072
Dystonia
0001332
Percent of people who have these symptoms is not available through HPO
Absent speech
Absent speech development
Lack of language development
Lack of speech
No speech development
No speech or language development
Nonverbal

[ more ]

0001344
Autosomal dominant inheritance
0000006
Cerebral atrophy
Degeneration of cerebrum
0002059
Delayed myelination
0012448
Epileptic encephalopathy
0200134
Generalized tonic seizure
0010818
Global developmental delay
0001263
Hypoplasia of the corpus callosum
Underdevelopment of part of brain called corpus callosum
0002079
Hypsarrhythmia
0002521

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

    Social Networking Websites

      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.

      In-Depth Information

      • 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. 

        References

        1. Danti FR, Galosi S, Romani M, et al. GNAO1 encephalopathy: Broadening the phenotype and evaluating treatment and outcome. Neurology: Genetics. 2017; 3(2):143. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5362187/.
        2. Marcé-Grau A, Dalton J, López-Pisón J, et al. GNAO1 encephalopathy: further delineation of a severe neurodevelopmental syndrome affecting females. Orphanet Journal of Rare Diseases. 2016; 11:38. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4830060/.
        3. Feng H, Sjögren B, Karaj B, Shaw V, Gezer A & Neubig RR. Movement disorder in GNAO1 encephalopathy associated with gain-of-function mutations. Neurology. August 22, 2017; 89(8):762-770. https://www.ncbi.nlm.nih.gov/pubmed/28747448.
        4. About GNAO1. The Bow Foundation. https://gnao1.org/.