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GTR Home > Conditions/Phenotypes > Congenital myotonia, autosomal dominant form

Congenital myotonia, autosomal dominant form

Synonyms
Myotonia congenita autosomal dominant; Thomsen disease; Thomsen's disease

Summary

Excerpted from the GeneReview: Myotonia Congenita
Myotonia congenita is characterized by muscle stiffness present from childhood; all striated muscle groups including the extrinsic eye muscles, facial muscles, and tongue may be involved. Stiffness is relieved by repeated contractions of the muscle (the "warm-up" phenomenon). Muscles are usually hypertrophic. Whereas autosomal recessive (AR) myotonia congenita is often associated with more severe manifestations (such as progressive minor distal weakness and attacks of transient weakness brought on by movement after rest), autosomal dominant (AD) myotonia congenita is not. The age of onset varies: in AD myotonia congenita onset is usually in infancy or early childhood; in AR myotonia congenita the average age of onset is slightly older. In both AR and AD myotonia congenita onset may be as late as the third or fourth decade of life.
Full text of GeneReview (by section):
Summary
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Morten Dunø
John Vissing
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Available tests

42 tests are in the database for this condition.

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Clinical tests (42 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: CLC1, CLCN1
    Summary: chloride voltage-gated channel 1

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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