methylmalonic aciduria and homocystinuria type cblD
Findings
No curated finding names methylmalonic aciduria and homocystinuria type cblD yet. Everything below is reference data from Mondo, HPO and GenCC, not evidence about what affects it.
Definition
A form of methylmalonic acidemia with homocystinuria, an inborn error of vitamin B12 (cobalamin) metabolism characterized by variable biochemical, neurological and hematological manifestations.
Definition from the Mondo Disease Ontology (MONDO:0010185), read 2026-09-29. CC BY 4.0.
- Inheritance
- Autosomal recessive inheritance
- Onset and course
- Childhood onset
HPO, annotations 2026-09-02
Features
24 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.
- Brisk reflexesHPOHP:0001348
- 1 of 1 reported patient
- DysmetriaHPOHP:0001310
- 1 of 1 reported patient
- EncephalopathyHPOHP:0001298
- 1 of 1 reported patient
- Feeding difficultiesHPOHP:0011968
- 1 of 1 reported patient
- Global developmental delayHPOHP:0001263
- 1 of 1 reported patient
- Very frequent (80% to 99% of cases)
- HomocystinuriaHPOHP:0002156
- 3 of 3 reported patients
- Horizontal nystagmusHPO
Show the remaining 12
- SeizureHPOHP:0001250
- 2 of 2 reported patients
- Very frequent (80% to 99% of cases)
- Abnormality of movementHPOHP:0100022
- Very frequent (80% to 99% of cases)
- AnorexiaHPOHP:0002039
- Very frequent (80% to 99% of cases)
- Atypical behaviorHPOHP:0000708
- Very frequent (80% to 99% of cases)
- Failure to thriveHPOHP:0001508
- Very frequent (80% to 99% of cases)
- FatigueHPOHP:0012378
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.
- MMADHCHGNC:25221
- Definitive · G2P · Autosomal recessive · 2015
- Definitive · Natera · Autosomal recessive · 2023
- Strong · Labcorp Genetics (formerly Invitae) · Autosomal recessive · 2021
- Moderate · Ambry Genetics · Autosomal recessive · 2018
- Supportive · Orphanet · Autosomal recessive · 2021
Where it sits
Other names
5 names
Resolves to: methylmalonic aciduria and homocystinuria type cblD
- Also called
- cblD defectcobalamin D defectcobalamin d diseasecombined defect in adenosylcobalamin and methylcobalamin synthesis, type cblDmethylmalonic aciduria with homocystinuria, type cblD