congenital myopathy with myasthenic-like onset
Findings
No curated finding names congenital myopathy with myasthenic-like onset yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
Congenital myopathy with myasthenic-like onset is a rare, genetic, non-dystrophic myopathy characterized by fatigable muscle weakness associated with congenital myopathy. Patients present with axial hypotonia, myopathic facies with fatigable ptosis, feeding difficulties, delayed gross motor development and proximal limb weakness with a RYR1-related typical pattern of muscle involvement (i.e. severe involvement of the soleus muscle and sparring of the rectus femoris, sartorius, gracilis and semitendinous muscles). Scoliosis and frequent respiratory tract infections are additional observed features.
Definition from the Mondo Disease Ontology (MONDO:0018528), read 2026-09-29. CC BY 4.0.
Features
22 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.
- Fatigable weaknessHPOHP:0003473
- Very frequent (80% to 99% of cases)
- AreflexiaHPOHP:0001284
- Frequent (30% to 79% of cases)
- Axial hypotoniaHPOHP:0008936
- Frequent (30% to 79% of cases)
- Easy fatigabilityHPOHP:0003388
- Frequent (30% to 79% of cases)
- EMG: myopathic abnormalitiesHPOHP:0003458
- Frequent (30% to 79% of cases)
- Failure to thriveHPOHP:0001508
- Frequent (30% to 79% of cases)
- Feeding difficulties
Show the remaining 10
- Myopathic faciesHPOHP:0002058
- Frequent (30% to 79% of cases)
- MyopathyHPOHP:0003198
- Frequent (30% to 79% of cases)
- Proximal muscle weaknessHPOHP:0003701
- Frequent (30% to 79% of cases)
- PtosisHPOHP:0000508
- Frequent (30% to 79% of cases)
- Recurrent respiratory infectionsHPOHP:0002205
- Frequent (30% to 79% of cases)
- Scapular wingingHPOHP:0003691
- Frequent (30% to 79% of cases)
Genes
2 genes
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.
Where it sits
- A kind of