congenital myasthenic syndrome 2C
Findings
No curated finding names congenital myasthenic syndrome 2C yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A congenital myasthenic syndrome characterized by autosomal recessive inheritance of postsynaptic neuromuscular junction defects, early-onset muscle weakness, and low amplitude of the miniature endplate potential and current that has material basis in ompound heterozygous mutation in the CHRNB1 gene on chromosome 17p13.
Definition from the Mondo Disease Ontology (MONDO:0014582), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Congenital onset
HPO, annotations 2026-09-02
Features
4 features
What the disease is reported to present with, and how often among people who have it — never how often a feature means the disease. HPO, annotations 2026-09-02.
- EMG: decremental response of compound muscle action potential to repetitive nerve stimulationHPOHP:0003403
- 1 of 1 reported patient
- Feeding difficultiesHPOHP:0011968
- 3 of 3 reported patients
- Respiratory insufficiencyHPOHP:0002093
- 3 of 3 reported patients
- Anti-neuromuscular Junction acetylcholine receptor antibody positivityHPOHP:0030208
- 0 of 1 reported patient
Genes
1 gene
Germline variants in the gene encoding each protein, as classified by GenCC submitters, each in their own words. Limited, disputed and refuted submissions are listed too.
- CHRNB1HGNC:1961
- Definitive · ClinGen · Autosomal recessive · 2025
- Definitive · G2P · Autosomal recessive · 2021
- Definitive · G2P · Autosomal dominant · 2021
- Strong · Genomics England PanelApp · Autosomal recessive · 2021
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2020
- Moderate · Ambry Genetics · Autosomal dominant · 2018
Where it sits
Other names
2 names
Resolves to: congenital myasthenic syndrome 2C
- Also called
- CMS2Ccongenital myasthenic syndrome type 2C