GP1BB
Chr 22ARglycoprotein Ib platelet subunit beta
Also known as: BDPLT1, BS, CD42C, GP-Ib beta, GPIBB, GPIbbeta
The GP1BB gene encodes the beta subunit of platelet glycoprotein Ib, which forms part of the GPIb-V-IX receptor complex that binds von Willebrand factor and mediates platelet adhesion in arterial circulation. Mutations cause Bernard-Soulier syndrome type B and isolated giant platelet disorder, both characterized by bleeding disorders due to defective platelet function. These conditions follow autosomal recessive inheritance.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Mild missense constraint
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.
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
GP1BB · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
No active trials found for this gene.
Search ClinicalTrials.gov →External Resources
Links to major genomics databases and tools