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Disease Profile

Spinocerebellar ataxia 34

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 / 1 000 000

< 331

US Estimated

< 514

Europe Estimated

Age of onset

Adolescent

ICD-10

G11.1

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)

SCA34; Giroux Barbeau Syndrome; Erythrokeratodermia ataxia;

Categories

Congenital and Genetic Diseases; Nervous System Diseases; Skin Diseases

Summary

The following summary is from Orphanet, a European reference portal for information on rare diseases and orphan drugs.
orphanet

Orpha Number: 1955

Definition
An autosomal dominant cerebellar ataxia type I that is characterized by papulosquamous, ichthyosiform plaques on the limbs appearing shortly after birth and later manifestations including progressive ataxia, dysarthria, nystagmus and decreased reflexes.

Epidemiology
To date the disorder has been reported in 45 patients including 4 asymptomatic carriers, from one French-Canadian family and three Japanese families.

Clinical description
Disease onset occurs from shortly after birth to adolescence with the appearance of papulosquamous, ichthyosiform plaques on the limbs, which are often only present in the winter. After the age of 25 years they tend to disappear completely. Progressive ataxia, dysarthria, decreased reflexes, and nystagmus are further clinical signs of the disease that occur after the onset of skin manifestations, generally from the third to fifth decade of life. Patients occasionally present with autonomic dysfunction and pyramidal signs. Cerebellar and pontine atrophy is visible with magnetic resonance imaging (MRI) in individuals who develop cerebellar ataxia.

Etiology
The disorder is due to a mutation in the ELOVL4 gene (6q14).

Diagnostic methods
Diagnosis is based on characteristic clinical findings (skin lesions occurring shortly after birth and adult-onset slowly progressive cerebellar ataxia), and on the molecular genetic testing. Mutations in the ELOVL4 gene confirms diagnosis of SCA34. Magnetic resonance imaging usually shows marked atrophy of the cerebellum and pontine which is sometimes accompanied by Hot Cross Bun sign that is common in cerebellar type of multiple system atrophy.

Differential diagnosis
Differential diagnoses include other forms of autosomal dominant cerebellar ataxia. From the view point of radiological findings, multiple system atrophy is important in differential diagnosis, especially in patients who also develop autonomic dysfunction.

Antenatal diagnosis
Antenatal diagnosis is possible in families with a known ELOVL4 mutation.

Genetic counseling
The disorder is inherited in an autosomal dominant manner and genetic counseling is possible. Genetic counseling should be proposed to individuals having the disease-causing mutation informing them that there is 50% risk of passing the mutation to offspring.

Management and treatment
Treatment is only supportive. Physical activity should be maintained as much as possible with the help of prosthetic devices. Motorized chairs/scooters are eventually necessary. Speech therapy and communication devices should be offered to those with severe dysarthria.

Prognosis
Disease progression is slow; the patients require cane or walker in their late 60s, and wheelchair in their 70s.

Visit the Orphanet disease page for more resources.

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
80%-99% of people have these symptoms
Dry skin
0000958
Dysarthria
Difficulty articulating speech
0001260
Dysdiadochokinesis
Difficulty performing quick and alternating movements
0002075
Gait disturbance
Abnormal gait
Abnormal walk
Impaired gait

[ more ]

0001288
Hypohidrosis
Decreased ability to sweat
Decreased sweating
Sweating, decreased

[ more ]

0000966
Hyporeflexia
Decreased reflex response
Decreased reflexes

[ more ]

0001265
Macule
Flat, discolored area of skin
0012733
Nystagmus
Involuntary, rapid, rhythmic eye movements
0000639
Papule
0200034
Progressive cerebellar ataxia
0002073
Urticaria
Hives
0001025
5%-29% of people have these symptoms
Abnormality of the musculature
Muscular abnormality
0003011
Facial asymmetry
Asymmetry of face
Crooked face
Unsymmetrical face

[ more ]

0000324
Fasciculations
Muscle twitch
0002380
Intention tremor
0002080
Spasticity
Involuntary muscle stiffness, contraction, or spasm
0001257
Strabismus
Cross-eyed
Squint
Squint eyes

[ more ]

0000486
1%-4% of people have these symptoms
Peripheral axonal neuropathy
0003477
Percent of people who have these symptoms is not available through HPO
Abnormal pyramidal sign
0007256
Abnormality of the skin
0000951
Autosomal dominant inheritance
0000006
Cerebellar atrophy
Degeneration of cerebellum
0001272
Gait ataxia
Inability to coordinate movements when walking
0002066
Hyperkeratosis
0000962
Hyperreflexia
Increased reflexes
0001347
Impaired smooth pursuit
0007772
Incomplete penetrance
0003829
Limb ataxia
0002070
Supranuclear gaze palsy
0000605

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.

    In-Depth Information

    • 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 Spinocerebellar ataxia 34. Click on the link to view a sample search on this topic.