MMAA

Chr 4

metabolism of cobalamin associated A

Also known as: cblA

NCBI Gene: 166785ENSG00000151611UniProt: Q8IVH4

The protein encoded by this gene is involved in the translocation of cobalamin into the mitochondrion, where it is used in the final steps of adenosylcobalamin synthesis. Adenosylcobalamin is a coenzyme required for the activity of methylmalonyl-CoA mutase. Defects in this gene are a cause of methylmalonic aciduria. [provided by RefSeq, Jul 2008]

GeneReviewsResearchGenerating clinical summary…

Primary Disease Associations & Inheritance

UniProtMethylmalonic aciduria, cblA type

Clinical highlights

Gene-disease validity (ClinGen)
methylmalonic aciduria, cblA type · ARDefinitivesufficient evidence for diagnostic panels
Interpreting a novel variant
Loss of function is the curated mechanism (Gene2Phenotype), though the gene is not strongly LoF-constrained in the population — weigh truncating variants against that tolerance.Curated gene-level mechanism — a prior for triage, not a per-variant call.
0
Active trials
9
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
1.29
LOEUF
LOF
Mechanism· G2P
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GeneReview available — MMAA
Authoritative clinical overview · Recommended first read
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Some data sources returned errors (1)

omim: Error: OMIM fetch failed: 429

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
Tolerant — LoF & missense variants common in population
LoF Constraint?
1.29LOEUF
pLI 0.000
Z-score 0.49
OE 0.89 (0.62–1.29)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
0.33Z-score
OE missense 0.94 (0.84–1.05)
209 obs / 222.9 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.89 (0.62–1.29)
0≤0.351.4
Missense OE?0.94 (0.84–1.05)
0≤0.61.4
Synonymous OE?0.98
0≤1.21.6
LoF obs/exp: 20 / 22.5Missense obs/exp: 209 / 222.9Syn Z: 0.13

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

MMAA · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

ClinicalTrials.gov

No active trials found for this gene.

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External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients