SLC18A1

Chr 8

solute carrier family 18 member A1

Also known as: CGAT, VAT1, VMAT1

The vesicular monoamine transporter 1 protein accumulates monoamines (including serotonin, dopamine, and norepinephrine) into synaptic vesicles by exchanging monoamines for protons, which is essential for proper neurotransmitter release. Mutations cause vesicular monoamine transporter 1 deficiency, a rare movement disorder with infantile onset featuring hypotonia, developmental delay, and movement abnormalities. This gene follows autosomal recessive inheritance and shows very low constraint against loss-of-function variants.

Summary from RefSeq, UniProt
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0
Active trials
6
Pubs (1 yr)
80
P/LP submissions
0%
P/LP missense
1.59
LOEUF
Multiple*
Mechanism· predicted
Clinical SummarySLC18A1
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
80 unique Pathogenic / Likely Pathogenic· 123 VUS of 214 total submissions

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.59LOEUF
pLI 0.000
Z-score -0.78
OE 1.17 (0.871.59)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-2.38Z-score
OE missense 1.39 (1.281.50)
420 obs / 303.2 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE1.17 (0.871.59)
00.351.4
Missense OE1.39 (1.281.50)
00.61.4
Synonymous OE1.25
01.21.6
LoF obs/exp: 29 / 24.8Missense obs/exp: 420 / 303.2Syn Z: -2.08
DN
0.75top 25%
GOF
0.72top 25%
LOF
0.3065th %ile

This gene has evidence for multiple mechanisms of pathogenicity (dominant-negative and gain-of-function). Both the Badonyi & Marsh prediction and the broader genomic evidence point to dominant-negative as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

DNprediction above median
GOFprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

214 submitted variants in ClinVar

Classification Summary

Pathogenic77
Likely Pathogenic3
VUS123
Likely Benign5
77
Pathogenic
3
Likely Pathogenic
123
VUS
5
Likely Benign

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
77
0
77
Likely Pathogenic
0
0
3
0
3
VUS
1
113
9
0
123
Likely Benign
0
4
0
1
5
Benign
0
0
0
0
0
Total1117891208

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

Protein Context — Lollipop Plot

SLC18A1 · 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

No active trials found for this gene.

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Clinical Literature
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