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GTR Home > Conditions/Phenotypes > Myasthenic syndrome, congenital, 7B, presynaptic, autosomal recessive

Summary

Autosomal recessive presynaptic congenital myasthenic syndrome-7B (CMS7B) is characterized by severe generalized muscle weakness apparent from birth; decreased fetal movements may be apparent in utero. Affected infants have generalized hypotonia with poor cry and feeding, head lag, and facial muscle weakness with ptosis. Some patients may have respiratory involvement. Electrophysiologic studies show decreased compound muscle action potentials (CMAPs) and a decremental response to repetitive nerve stimulation. Treatment with 3,4-diaminopyridine and pyridostigmine may result in clinical improvement (summary by Bauche et al., 2020). [from OMIM]

Available tests

3 tests are in the database for this condition.

Genes See tests for all associated and related genes

  • Also known as: CMS7, CMS7A, CMS7B, MYSPC, SytII, SYT2
    Summary: synaptotagmin 2

Clinical features

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