TUBA4A

Chr 2ADAR

tubulin alpha 4a

Also known as: ALS22, CMYO26, FTDALS9, H2-ALPHA, OZEMA23, SPAX11, TUBA1

This gene encodes an alpha tubulin protein that forms heterodimers with beta tubulin to constitute microtubules, the major structural components of the cellular cytoskeleton. Mutations cause autosomal dominant spastic ataxia, frontotemporal dementia with or without amyotrophic lateral sclerosis, and autosomal recessive congenital myopathy, affecting the nervous system and skeletal muscle. The gene shows moderate constraint against loss-of-function variants (LOEUF 0.62), and inheritance patterns vary by phenotype with both dominant and recessive forms described.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt
DNmechanismAD/ARLOEUF 0.624 OMIM phenotypes
Clinical SummaryTUBA4A
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Gene-Disease Validity (ClinGen)
amyotrophic lateral sclerosis type 22 · ADModerate

Moderate evidence — consider for supplementary testing

2 total gene-disease associations curated

Population Constraint (gnomAD)
Constrained for loss-of-function variants (OE-LoF 0.27) despite low pLI — interpret in context.
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ClinVar Variants
53 unique Pathogenic / Likely Pathogenic· 38 VUS of 156 total submissions
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GeneReview available — TUBA4A
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Missense constrained — critical functional residues
LoF Constraint
0.62LOEUF
pLI 0.160
Z-score 2.60
OE 0.27 (0.130.62)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
3.30Z-score
OE missense 0.44 (0.380.51)
120 obs / 273.8 exp
Constrained

Highly missense-constrained (top ~0.1%)

Observed / Expected Ratios
LoF OE0.27 (0.130.62)
00.351.4
Missense OE0.44 (0.380.51)
00.61.4
Synonymous OE0.99
01.21.6
LoF obs/exp: 4 / 14.8Missense obs/exp: 120 / 273.8Syn Z: 0.07
DN
0.78top 25%
GOF
0.4875th %ile
LOF
0.3746th %ile

The highest-scoring mechanism for this gene is dominant-negative.

DNprediction above median · 1 literature citation

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

DNTUBA4A mutants act as dominant negatives to alter microtubule dynamics and stabilityPMID:25374358

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

156 submitted variants in ClinVar

Classification Summary

Pathogenic44
Likely Pathogenic9
VUS38
Likely Benign45
Benign16
Conflicting1
44
Pathogenic
9
Likely Pathogenic
38
VUS
45
Likely Benign
16
Benign
1
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
2
10
32
0
44
Likely Pathogenic
4
3
2
0
9
VUS
3
28
6
1
38
Likely Benign
0
1
9
35
45
Benign
0
0
12
4
16
Conflicting
1
Total9426140153

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

View in ClinVar →

Protein Context — Lollipop Plot

TUBA4A · 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 →
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC