STXBP3

Chr 1

syntaxin binding protein 3

Also known as: MUNC18-3, MUNC18C, PSP, UNC-18C

STXBP3 encodes a protein that binds syntaxins and regulates calcium-dependent exocytosis, including insulin-dependent GLUT4 vesicle transport in adipocytes and neutrophil degranulation. The gene shows extremely high constraint against loss-of-function variants (pLI nearly 1.0), suggesting that heterozygous mutations would likely cause dominant disease, though specific associated disorders have not yet been established. Clinical presentations would likely involve metabolic dysfunction given the protein's role in glucose transport regulation.

OMIMResearchSummary from RefSeq, UniProt
LOEUF 0.59
Clinical SummarySTXBP3
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Moderate LoF intolerance
LoF Constraint
0.59LOEUF
pLI 0.000
Z-score 3.49
OE 0.38 (0.250.59)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint
1.76Z-score
OE missense 0.71 (0.640.80)
216 obs / 302.3 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.38 (0.250.59)
00.351.4
Missense OE0.71 (0.640.80)
00.61.4
Synonymous OE0.85
01.21.6
LoF obs/exp: 14 / 36.9Missense obs/exp: 216 / 302.3Syn Z: 1.18

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

STXBP3 · protein map & ClinVar variants

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

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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Clinical Literature
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Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC