TUBB2B
Chr 6ADtubulin beta 2B class IIb
Also known as: CDCBM7, PMGYSA, bA506K6.1
The encoded protein is a beta-tubulin isoform that binds GTP and serves as a major component of microtubules in the cytoskeleton. Mutations cause autosomal dominant asymmetric polymicrogyria and complex cortical dysplasia with other brain malformations. The high pLI score (0.99) indicates the gene is extremely intolerant to loss-of-function mutations, suggesting haploinsufficiency as the likely pathogenic mechanism.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly LoF-intolerant (top ~10% of genes)
Extremely missense-constrained (top ~0.01%)
This gene has evidence for multiple mechanisms of pathogenicity (loss-of-function and dominant-negative). Both the Badonyi & Marsh prediction and the broader genomic evidence point to loss-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.
Literature Evidence
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312. Mechanism ranking also informed by gnomAD constraint, ClinVar, and ClinGen data.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
TUBB2B · 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