MOLECULAR MEDICINE, NEUROLOGY
A congenital myasthenic syndrome* (OMIM:601462) caused by kinetic abnormalities of the AChR, resulting in prolonged endplate currents and prolonged AChR channel opening episodes.
*Congenital myasthenic syndromes are characterised by muscle weakness affecting axial and limb muscles with hypotonia in early-onset forms, ocular muscles–leading to ptosis and ophthalmoplegia, and facial and bulbar muscles–affecting sucking and swallowing, leading to dysphonia.
Molecular pathology Defects of CHRNA1, which encodes cholinergic receptor—nicotinic—alpha 1 (muscle), a subunit of acetylcholine receptor, cause myasthenic syndrome—congenital—1A—slow-channel.
Synonyms Myasthenic syndrome—congenital—postsynaptic—slow channel, myasthenic syndrome—congenital—type IIa, SCCMS, slow-channel congenital myasthenic syndrome