ST3GAL3

Chr 1AR

ST3 beta-galactoside alpha-2,3-sialyltransferase 3

Also known as: DEE15, EIEE15, MRT12, SIAT6, ST3GALII, ST3Gal III, ST3GalIII, ST3N

The protein is a sialyltransferase that catalyzes the transfer of sialic acid from CMP-sialic acid to galactose-containing substrates in the Golgi apparatus. Mutations cause autosomal recessive developmental and epileptic encephalopathy 15 and intellectual developmental disorder, autosomal recessive 12. The pathogenic mechanism involves dominant-negative effects disrupting normal protein function.

OMIMResearchSummary from RefSeq, OMIM, UniProt, Mechanism
DNmechanismARLOEUF 0.622 OMIM phenotypes
Clinical SummaryST3GAL3
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Gene-Disease Validity (ClinGen)
complex neurodevelopmental disorder · ARModerate

Moderate evidence — consider for supplementary testing

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

Tolerant — LoF & missense variants common in population
LoF Constraint
0.62LOEUF
pLI 0.003
Z-score 3.00
OE 0.36 (0.210.62)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
1.50Z-score
OE missense 0.74 (0.650.83)
188 obs / 255.4 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.36 (0.210.62)
00.351.4
Missense OE0.74 (0.650.83)
00.61.4
Synonymous OE0.97
01.21.6
LoF obs/exp: 9 / 25.3Missense obs/exp: 188 / 255.4Syn Z: 0.27
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
strongST3GAL3-related intellectual developmental disorderOTHERAR

Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.

DN
0.6550th %ile
GOF
0.4875th %ile
LOF
0.2582th %ile

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

ST3GAL3 · 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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