MAN2B1
Chr 19ARmannosidase alpha class 2B member 1
Also known as: LAMAN, MANB
The encoded enzyme hydrolyzes terminal alpha-D-mannose residues in oligosaccharides during lysosomal degradation of N-linked glycoproteins. Mutations cause alpha-mannosidosis types I and II, a lysosomal storage disorder with autosomal recessive inheritance that affects multiple organ systems including the nervous system, skeleton, and immune system. This gene shows very low constraint against loss-of-function variants, consistent with its recessive inheritance pattern.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Typical tolerance to LoF variation
Mild missense constraint
ClinVar Variant Classifications
200 submitted variants in ClinVar
Classification Summary
Curated Variants Distribution
Classified variants from ClinVar · 5 ACMG categories
| Classification | LoF | Missense + Inframe | Non-coding | Synonymous | Total |
|---|---|---|---|---|---|
Pathogenic | 3 | 1 | 0 | 0 | 4 |
Likely Pathogenic | 24 | 0 | 0 | 0 | 24 |
VUS | 0 | 80 | 10 | 11 | 101 |
Likely Benign | 0 | 0 | 27 | 21 | 48 |
Benign | 0 | 0 | 0 | 0 | 0 |
| Total | 27 | 81 | 37 | 32 | 177 |
LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly
View in ClinVar →Protein Context — Lollipop Plot
MAN2B1 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
No active trials found for this gene.
Search ClinicalTrials.gov →External Resources
Links to major genomics databases and tools