PRB3

Chr 12

proline rich protein BstNI subfamily 3

Also known as: G1, PRG

The protein encoded by this gene is a basic proline-rich salivary glycoprotein that acts as a receptor for Gram-negative bacteria and provides oral defense against dietary polyphenols and pathogen infections. The gene is highly tolerant to loss-of-function variants based on constraint metrics, and no established Mendelian disease associations have been reported for this salivary protein gene.

Summary from RefSeq, UniProt
Research Assistant →
0
Active trials
1
Pubs (1 yr)
0
P/LP submissions
P/LP missense
1.31
LOEUF
Multiple*
Mechanism· predicted
Clinical SummaryPRB3
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
1.31LOEUF
pLI 0.000
Z-score 0.73
OE 0.79 (0.501.31)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.99Z-score
OE missense 1.21 (1.081.35)
218 obs / 180.5 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.79 (0.501.31)
00.351.4
Missense OE1.21 (1.081.35)
00.61.4
Synonymous OE1.11
01.21.6
LoF obs/exp: 11 / 13.9Missense obs/exp: 218 / 180.5Syn Z: -0.65
DN
0.91top 5%
GOF
0.88top 5%
LOF
0.2971th %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

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

PRB3 · 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.

Search ClinicalTrials.gov →
Clinical Literature
Open Research Assistant →