GPX3

Chr 5

glutathione peroxidase 3

Also known as: GPx-P, GSHPx-3, GSHPx-P

The protein encoded by this gene belongs to the glutathione peroxidase family, members of which catalyze the reduction of organic hydroperoxides and hydrogen peroxide (H2O2) by glutathione, and thereby protect cells against oxidative damage. Several isozymes of this gene family exist in vertebrates, which vary in cellular location and substrate specificity. This isozyme is secreted, and is abundantly found in plasma. Downregulation of expression of this gene by promoter hypermethylation has been observed in a wide spectrum of human malignancies, including thyroid cancer, hepatocellular carcinoma and chronic myeloid leukemia. This isozyme is also a selenoprotein, containing the rare amino acid selenocysteine (Sec) at its active site. Sec is encoded by the UGA codon, which normally signals translation termination. The 3' UTRs of selenoprotein mRNAs contain a conserved stem-loop structure, designated the Sec insertion sequence (SECIS) element, that is necessary for the recognition of UGA as a Sec codon, rather than as a stop signal. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Jul 2016]

OMIMResearchGenerating clinical summary…
MultiplemechanismLOEUF 0.80
Clinical SummaryGPX3
Population Constraint (gnomAD)
Low constraint (pLI 0.05) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
30 VUS of 38 total submissions
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Clinical Trials
3 active or recruiting trials — potential therapeutic options may be available

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint?
0.80LOEUF
pLI 0.051
Z-score 2.04
OE 0.35 (0.170.80)
Tolerant

Typical tolerance to LoF variation

Missense Constraint?
0.57Z-score
OE missense 0.86 (0.741.01)
114 obs / 132.3 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.35 (0.170.80)
00.351.4
Missense OE?0.86 (0.741.01)
00.61.4
Synonymous OE?1.03
01.21.6
LoF obs/exp: 4 / 11.4Missense obs/exp: 114 / 132.3Syn Z: -0.15

This gene — mechanism propensity

DN
0.74top 25%
GOF
0.6833th %ile
LOF
0.1895th %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

38 submitted variants in ClinVar

Classification Summary

VUS30
30
VUS

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
0
0
0
0
0
Likely Pathogenic
0
0
0
0
0
VUS
0
30
0
0
30
Likely Benign
0
0
0
0
0
Benign
0
0
0
0
0
Total0300030

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

View in ClinVar →

10 pathogenic / likely-pathogenic (of 11) ClinVar copy-number / structural variants overlap GPX3 — these span large chromosomal regions, not the gene specifically, and are excluded from the counts above. Explore in CNV tools →

Protein Context — Lollipop Plot

GPX3 · protein map & ClinVar variants

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