Dataset Information

Electrophysiologic features of SYT2 mutations causing a treatable neuromuscular syndrome.

ABSTRACT:

Objectives

To describe the clinical and electrophysiologic features of synaptotagmin II (SYT2) mutations, a novel neuromuscular syndrome characterized by foot deformities and fatigable ocular and lower limb weakness, and the response to modulators of acetylcholine release.

Methods

We performed detailed clinical and neurophysiologic assessment in 2 multigenerational families with dominant SYT2 mutations (c.920T>G [p.Asp307Ala] and c.923G>A [p.Pro308Leu]). Serial clinical and electrophysiologic assessments were performed in members of one family treated first with pyridostigmine and then with 3,4-diaminopyridine.

Results

Electrophysiologic testing revealed features indicative of a presynaptic deficit in neurotransmitter release with posttetanic potentiation lasting up to 60 minutes. Treatment with 3,4-diaminopyridine produced both a clinical benefit and an improvement in neuromuscular transmission.

Conclusion

SYT2 mutations cause a novel and potentially treatable complex presynaptic congenital myasthenic syndrome characterized by motor neuropathy causing lower limb wasting and foot deformities, with reflex potentiation following exercise and a uniquely prolonged period of posttetanic potentiation.

SUBMITTER: Whittaker RG

PROVIDER: S-EPMC4664120 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Publications

Electrophysiologic features of SYT2 mutations causing a treatable neuromuscular syndrome.

Whittaker Roger G RG Herrmann David N DN Bansagi Boglarka B Hasan Bashar Awwad Shiekh BA Lofra Robert Muni RM Logigian Eric L EL Sowden Janet E JE Almodovar Jorge L JL Littleton J Troy JT Zuchner Stephan S Horvath Rita R Lochmüller Hanns H

Neurology 20151030 22

<h4>Objectives</h4>To describe the clinical and electrophysiologic features of synaptotagmin II (SYT2) mutations, a novel neuromuscular syndrome characterized by foot deformities and fatigable ocular and lower limb weakness, and the response to modulators of acetylcholine release.<h4>Methods</h4>We performed detailed clinical and neurophysiologic assessment in 2 multigenerational families with dominant SYT2 mutations (c.920T>G [p.Asp307Ala] and c.923G>A [p.Pro308Leu]). Serial clinical and electr ...[more]

PMID: 26519543

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Dataset Information

Electrophysiologic features of SYT2 mutations causing a treatable neuromuscular syndrome.

Objectives

Methods

Results

Conclusion

Publications

Electrophysiologic features of SYT2 mutations causing a treatable neuromuscular syndrome.

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