KBTBD8

Chr 3

kelch repeat and BTB domain containing 8

Also known as: TA-KRP, TAKRP

KBTBD8 encodes a substrate-specific adapter protein that forms part of an E3 ubiquitin ligase complex and regulates neural crest specification by modulating ribosomal processing through monoubiquitination of NOLC1 and TCOF1. Mutations cause autosomal recessive developmental delay with dysmorphic facies and dental anomalies, reflecting the protein's critical role in neural crest development. The gene shows tolerance to loss-of-function variants (pLI near 0), consistent with the recessive inheritance pattern observed clinically.

OMIMResearchSummary from RefSeq, UniProt
MultiplemechanismLOEUF 0.82
Clinical SummaryKBTBD8
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
0.82LOEUF
pLI 0.000
Z-score 2.21
OE 0.51 (0.330.82)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
1.25Z-score
OE missense 0.80 (0.720.89)
258 obs / 321.3 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.51 (0.330.82)
00.351.4
Missense OE0.80 (0.720.89)
00.61.4
Synonymous OE0.96
01.21.6
LoF obs/exp: 12 / 23.6Missense obs/exp: 258 / 321.3Syn Z: 0.30
DN
0.6453th %ile
GOF
0.6639th %ile
LOF
0.3065th %ile

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.

GOFprediction above median
DNprediction 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

KBTBD8 · 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 →
Key Publications
Landmark & review papers · by relevance
PubMed
Top 1 results · since 2015Search PubMed ↗