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Ocular anomalies-axonal neuropathy-developmental delay syndrome
Disease definition
A rare mitochondrial disease characterized by signs and symptoms within a phenotypic and metabolic spectrum that includes global developmental delay, hypotonia, intellectual disability, optic atrophy, axonal neuropathy, hypertrophic cardiomyopathy, lactic acidosis, and increased excretion of Krebs cycle intermediates. Other variable features are spasticity, seizures, ataxia, congenital cataract, and dysmorphic facial features. Age of onset is in the neonatal period or infancy.
ORPHA:496790
Classification level: Disorder- Synonym(s):
- Harel-Yoon syndrome
- Prevalence: <1 / 1 000 000
- Inheritance: -
- Age of onset: Neonatal, Infancy
- ICD-10: E88.8
- OMIM: 617183
- UMLS: -
- MeSH: -
- GARD: -
- MedDRA: -
A summary on this disease is available in Español (2020) Français (2020) Nederlands (2020)
Detailed information
Genetic Testing
- Guidance for genetic testing
- Français (2016, pdf) - ANPGM


Additional information
Further information on this disease
Patient-centred resources for this disease
Research activities on this disease
Specialised Social Services
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