Methylmalonic aciduria cblb type: genes and variants
Explore variant evidence for Methylmalonic aciduria cblb type across 1 analyzed protein (MMAB). Linked ClinVar records include 23 pathogenic or likely pathogenic variants, 68 variants of uncertain significance and 13 with conflicting classifications.
Coverage includes proteins already analyzed in CATVariant, not every gene involved in this condition. Database links are associations, not an assessment of clinical gene–disease validity. Computable evidence prioritizes variants for expert review and does not reclassify them. Source labels are pooled across this disease family.
Data updated 2026-10-11. Automated aggregation, not a clinical review date.
Download variant evidence (CSV)
Genes linked to Methylmalonic aciduria cblb type
MMAB: Corrinoid adenosyltransferase MMAB
A mitochondrial enzyme that converts cobalamin into adenosylcobalamin, the cofactor used by methylmalonyl-CoA mutase. Variants cause the cblB form of methylmalonic acidemia.
23 ClinVar pathogenic / likely pathogenic and 81 uncertain variants in MMAB have source records linked to Methylmalonic aciduria cblb type. Association strength is not clinical gene validity.
ClinVar pathogenic and likely pathogenic variants linked to Methylmalonic aciduria cblb type
| Variant | Position | Protein part | Clinical label |
|---|---|---|---|
| MMAB R186P | 186 | Pathogenic / likely pathogenic (★★) | |
| MMAB R190C | 190 | Pathogenic / likely pathogenic (★★) | |
| MMAB R186Q | 186 | Pathogenic / likely pathogenic (★★) | |
| MMAB V188M | 188 | Pathogenic / likely pathogenic (★★) | |
| MMAB R190G | 190 | Pathogenic / likely pathogenic (★★) | |
| MMAB R190H | 190 | Pathogenic / likely pathogenic (★★) | |
| MMAB R191G | 191 | Pathogenic / likely pathogenic (★★) | |
| MMAB R191Q | 191 | Pathogenic / likely pathogenic (★★) | |
| MMAB E193K | 193 | Pathogenic / likely pathogenic (★★) | |
| MMAB M1T | 1 | Pathogenic / likely pathogenic (★★) | |
| MMAB M1R | 1 | Pathogenic / likely pathogenic (★★) | |
| MMAB S174L | 174 | Pathogenic / likely pathogenic (★★) | |
| MMAB R194G | 194 | Pathogenic / likely pathogenic (★★) | |
| MMAB G97E | 97 | Pathogenic / likely pathogenic (★★) | |
| MMAB M1K | 1 | Pathogenic / likely pathogenic (★) | |
| MMAB M1L | 1 | Pathogenic / likely pathogenic (★) | |
| MMAB R191P | 191 | Pathogenic / likely pathogenic (★) | |
| MMAB A127D | 127 | Pathogenic / likely pathogenic (★) | |
| MMAB I96T | 96 | Pathogenic / likely pathogenic (★) | |
| MMAB V188G | 188 | Pathogenic / likely pathogenic | |
| MMAB E193Q | 193 | Pathogenic / likely pathogenic | |
| MMAB E154D | 154 | Pathogenic / likely pathogenic | |
| MMAB S217I | 217 | Pathogenic / likely pathogenic |
Uncertain variants prioritized for review in Methylmalonic aciduria cblb type
| Variant | Position | Protein part | Clinical label | Evidence |
|---|---|---|---|---|
| MMAB R190L | 190 | Uncertain (★) | +6: 10 other pathogenic changes within 3 positions; R190G at the same position is pathogenic; not seen in the gnomAD population database; AlphaMissense 0.98 | |
| MMAB R186G | 186 | Uncertain (★) | +6: 4 other pathogenic changes within 3 positions; R186P at the same position is pathogenic; not seen in the gnomAD population database; AlphaMissense 0.64 |
Diseases related to Methylmalonic aciduria cblb type
- Methylmalonic acidemia, also linked to MMAB
Frequently asked questions
Which genes have records linked to Methylmalonic aciduria cblb type?
This view contains 1 analyzed proteins: MMAB. Links come from clinical records and association databases. They do not imply that every listed gene is a validated cause, and missing genes may not yet be analyzed.
What do the clinical classifications mean?
Linked records include 23 pathogenic or likely pathogenic variants, 68 variants of uncertain significance and 13 with conflicting classifications. Labels summarize source records; multi-condition records may not make a separate assertion for this disease. Check the original record and review status.
Does the evidence score change a VUS classification?
No. 2 VUS or conflicting variants reach the likely-pathogenic points range on the computable criteria available here. This is a research prioritization signal, not a clinical classification. Patient, family and other required evidence may be missing.
Can I download the variant evidence?
Download the CSV for all 107 variants in the selected disease scope, including clinical labels, review status, evidence criteria, predictor scores, functional measurements and population frequency where available.
About this data
Variant–disease links come from ClinVar, Open Targets and UniProt, pooled from eligible public CATVariant analyses of each human protein. Evidence scores use the ACMG/AMP Bayesian points scale with computable criteria only (position among known disease variants, rarity in gnomAD, calibrated predictors, deep mutational scanning); there is no family or patient data, so they prioritise variants for expert review and never classify them.
Download every variant as CSV · Browse all diseases · Methods · About the Center