SLC19A2

Chr 1AR

solute carrier family 19 member 2

Also known as: TC1, THMD1, THT1, THTR1, TRMA

This gene encodes a high-affinity thiamine transporter that mediates cellular uptake of thiamine (vitamin B1) and also transports pyridoxine in a proton-dependent manner. Mutations cause thiamine-responsive megaloblastic anemia syndrome, an autosomal recessive disorder characterized by the triad of diabetes mellitus, megaloblastic anemia, and sensorineural deafness. The gene shows low constraint against loss-of-function variants (pLI 0.0004), consistent with its recessive inheritance pattern.

OMIMResearchSummary from RefSeq, OMIM, UniProt
MultiplemechanismARLOEUF 0.761 OMIM phenotype
Clinical SummarySLC19A2
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
0.76LOEUF
pLI 0.000
Z-score 2.36
OE 0.44 (0.260.76)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
0.19Z-score
OE missense 0.97 (0.871.07)
263 obs / 271.9 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.44 (0.260.76)
00.351.4
Missense OE0.97 (0.871.07)
00.61.4
Synonymous OE0.96
01.21.6
LoF obs/exp: 9 / 20.6Missense obs/exp: 263 / 271.9Syn Z: 0.30
DN
0.74top 25%
GOF
0.74top 25%
LOF
0.2582th %ile

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

GOFprediction above median
DNprediction 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

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

SLC19A2 · 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.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →