adult-onset chronic progressive external ophthalmoplegia with mitochondrial myopathy

MONDO:0018002Mondo

Findings

No curated finding names adult-onset chronic progressive external ophthalmoplegia with mitochondrial myopathy yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.

Adult-onset chronic progressive external ophthalmoplegia with mitochondrial myopathy is a rare mitochondrial disease characterized by adult onset of progressive external ophthalmoplegia, exercise intolerance, muscle weakness, manifestations of spinocerebellar ataxia (e.g. impaired gait, dysarthria) and mild motor peripheral neuropathy. Respiratory insufficiency has been reported in some cases.

Definition from the Mondo Disease Ontology (MONDO:0018002), read 2026-09-29. CC BY 4.0.

Features

32 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.

Progressive external ophthalmoplegiaHPOHP:0000590
- Obligate (100% of cases)
Exercise intoleranceHPOHP:0003546
- Very frequent (80% to 99% of cases)
Limb muscle weaknessHPOHP:0003690
- Very frequent (80% to 99% of cases)
Areflexia of lower limbsHPOHP:0002522
- Frequent (30% to 79% of cases)
Bilateral ptosisHPOHP:0001488
- Frequent (30% to 79% of cases)
Difficulty climbing stairsHPOHP:0003551
- Frequent (30% to 79% of cases)
Dysarthria

Show the remaining 20

High palateHPOHP:0000218
- Frequent (30% to 79% of cases)
MyalgiaHPOHP:0003326
- Frequent (30% to 79% of cases)
Respiratory insufficiency due to muscle weaknessHPOHP:0002747
- Frequent (30% to 79% of cases)
Skeletal muscle atrophyHPOHP:0003202
- Frequent (30% to 79% of cases)
Weakness of facial musculatureHPOHP:0030319
- Frequent (30% to 79% of cases)
Abnormal atrioventricular conductionHPOHP:0005150
- Occasional (5% to 29% 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.

RNASEH1HGNC:18466
- Supportive · Orphanet · Autosomal dominant · 2021
RRM2BHGNC:17296
- Supportive · Orphanet · Autosomal dominant · 2021

Where it sits

A kind of: inborn mitochondrial myopathy
mitochondrial oxidative phosphorylation disorder
Narrower terms (1): progressive external ophthalmoplegia with mitochondrial DNA deletions, autosomal recessive 2

Other names

1 name

Resolves to: adult-onset chronic progressive external ophthalmoplegia with mitochondrial myopathy

Also called: adult-onset CPEO with mitochondrial myopathy