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GTR Home > Conditions/Phenotypes > Myasthenic syndrome, congenital, 1B, fast-channel

Myasthenic syndrome, congenital, 1B, fast-channel

Synonyms
Fast-Channel Congenital Myasthenia Syndrome

Summary

Fast-channel congenital myasthenic syndrome (FCCMS) is a disorder of the postsynaptic neuromuscular junction (NMJ) characterized by early-onset progressive muscle weakness. The disorder results from kinetic abnormalities of the acetylcholine receptor (AChR) channel, specifically from abnormally brief opening and activity of the channel, with a rapid decay in endplate current and a failure to reach the threshold for depolarization. Treatment with pyridostigmine or amifampridine may be helpful; quinine, quinidine, and fluoxetine should be avoided (summary by Sine et al., 2003 and Engel et al., 2015). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462). [from OMIM]

Available tests

54 tests are in the database for this condition.

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Clinical tests (54 available)

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: ACHRA, ACHRD, CHRNA, CMS1A, CMS1B, CMS2A, FCCMS, SCCMS, CHRNA1
    Summary: cholinergic receptor nicotinic alpha 1 subunit

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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