SLC5A3

Chr 21

solute carrier family 5 member 3

Also known as: BCW2, SMIT, SMIT1, SMIT2

NCBI Gene: 6526ENSG00000198743UniProt: P53794OMIM: 600444

Enables myo-inositol:sodium symporter activity; potassium channel regulator activity; and transmembrane transporter binding activity. Predicted to be involved in monosaccharide transmembrane transport and myo-inositol import across plasma membrane. Predicted to act upstream of or within several processes, including inositol metabolic process; positive regulation of reactive oxygen species biosynthetic process; and regulation of respiratory gaseous exchange. Located in perinuclear region of cytoplasm and plasma membrane. [provided by Alliance of Genome Resources, Jun 2026]

OMIMResearchGenerating clinical summary…

Clinical highlights

Interpreting a novel variant
This gene is strongly intolerant of loss-of-function variation in the population, so LoF variants warrant close attention. No curated mechanism annotation is available — see the mechanism card for the computational prediction and its caveats.Based on population constraint only.
0
Active trials
9
Pubs (1 yr)
—
P/LP submissions
—
P/LP missense
0.32
LOEUF· LoF intol.
Multiple*
Mechanism· predicted

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

gnomAD
LoF intolerant — likely haploinsufficient
LoF Constraint?
0.32LOEUF
pLI 0.967
Z-score 3.66
OE 0.10 (0.04–0.32)
Highly constrained

Highly LoF-intolerant (top ~10% of genes)

Missense Constraint?
2.76Z-score
OE missense 0.61 (0.55–0.68)
247 obs / 403.0 exp
Mild constraint

Moderately missense-constrained (top ~2.5%)

Observed / Expected Ratios?
LoF OE?0.10 (0.04–0.32)
0≤0.351.4
Missense OE?0.61 (0.55–0.68)
0≤0.61.4
Synonymous OE?1.16
0≤1.21.6
LoF obs/exp: 2 / 19.4Missense obs/exp: 247 / 403.0Syn Z: -1.55

ClinVar Variant Classifications

0 submitted variants in ClinVar

ClinVar

Protein Context — Lollipop Plot

SLC5A3 · 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

ClinicalTrials.gov

No active trials found for this gene.

Search ClinicalTrials.gov →

External Resources

Links to major genomics databases and tools

Franklin by Genoox
AI-powered variant curation and clinical analysis
DECIPHER
Genomic variants and phenotypes in rare disease patients