MASP1
Chr 3MBL associated serine protease 1
Also known as: 3MC1, CRARF, CRARF1, MAP-1, MAP1, MASP, MASP-3, MASP3
This gene encodes a serine protease that activates the lectin pathway of complement activation and may also function in coagulation by cleaving fibrinogen and factor XIII. Mutations cause 3MC syndrome 1, an autosomal recessive disorder characterized by multiple congenital anomalies affecting craniofacial development, skeletal system, and other organ systems. The gene shows very low constraint to loss-of-function variants, consistent with its recessive inheritance pattern.
Definitive — sufficient evidence for diagnostic panels
Some data sources returned errors (1)
omim: Error: OMIM fetch failed: 429
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Typical tolerance to LoF variation
Tolerant to missense variation
Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.
The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
MASP1 · 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