ARID4B

Chr 1

AT-rich interaction domain 4B

Also known as: BCAA, BRCAA1, RBBP1L1, RBP1L1, SAP180

The protein functions as a transcriptional repressor and is a subunit of the histone deacetylase-dependent SIN3A transcriptional corepressor complex, regulating gene expression involved in cellular proliferation, differentiation, and apoptosis. Mutations cause autosomal dominant intellectual disability with developmental delay, and the gene is highly intolerant to loss-of-function variants. The condition affects neurodevelopment and may include additional features given the protein's broad role in transcriptional regulation.

OMIMResearchSummary from RefSeq, UniProt
LOFmechanismLOEUF 0.19
Clinical SummaryARID4B
Population Constraint (gnomAD)
Highly constrained gene — heterozygous loss-of-function variants are very rare in the population (pLI 1.00). One damaged copy is likely sufficient to cause disease.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

LoF intolerant — likely haploinsufficient
LoF Constraint
0.19LOEUF
pLI 1.000
Z-score 6.67
OE 0.09 (0.050.19)
Highly constrained

Highly LoF-intolerant (top ~10% of genes)

Missense Constraint
2.29Z-score
OE missense 0.75 (0.690.80)
480 obs / 643.5 exp
Mild constraint

Moderately missense-constrained (top ~2.5%)

Observed / Expected Ratios
LoF OE0.09 (0.050.19)
00.351.4
Missense OE0.75 (0.690.80)
00.61.4
Synonymous OE0.91
01.21.6
LoF obs/exp: 6 / 63.2Missense obs/exp: 480 / 643.5Syn Z: 1.09
DN
0.2499th %ile
GOF
0.2198th %ile
LOF
0.84top 5%

The highest-scoring mechanism for this gene is loss-of-function (haploinsufficiency).

LOFprediction above median · LOEUF 0.19

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

ARID4B · 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.

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Clinical Literature
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