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Start free with EleplanMethylmalonic acidemia without homocystinuria
ORPHA:293355Clinical group
Also called Methylmalonic aciduria without homocystinuria
What it is
Methylmalonic acidemia is an inborn error of vitamin B12 metabolism characterized by gastrointestinal and neurometabolic manifestations resulting from decreased function of the mitochondrial enzyme methylmalonyl-CoA mutase.
Key facts
- Prevalence
- 1-9 / 100 000 (Europe)
- Age of onset
- All ages
- Inheritance
- Autosomal dominant, Autosomal recessive, X-linked dominant
- Classified as
- Clinical group
Prevalence figures describe populations, not individuals, and are often estimates from a single study. Where the figure is an incidence or a birth prevalence, it says so.
Genes reported in subtypes
Orphanet records this gene on 1 more specific entry under this disorder, not on this entry itself:
A well-studied disease is usually split into subtypes, and the gene is curated on whichever one the evidence belongs to. Open a subtype to see which gene goes with it.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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