ADARB1

Chr 21AR

adenosine deaminase RNA specific B1

Also known as: ADAR2, DRABA2, DRADA2, NEDHYMS, RED1

ADARB1 encodes an adenosine deaminase that catalyzes A-to-I RNA editing in double-stranded RNA, modifying the amino acid sequences of important neurotransmitter receptors including glutamate, serotonin, and GABA receptors. Biallelic mutations cause a neurodevelopmental disorder with hypotonia, microcephaly, and seizures, inherited in an autosomal recessive pattern. The gene is highly constrained against loss-of-function variants (LOEUF 0.399), indicating that haploinsufficiency is likely not tolerated in the general population.

OMIMResearchSummary from RefSeq, OMIM, UniProt
LOFmechanismARLOEUF 0.401 OMIM phenotype
Clinical SummaryADARB1
Population Constraint (gnomAD)
Moderately constrained gene (pLI 0.80) — some intolerance to loss-of-function variants.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Missense constrained — critical functional residues
LoF Constraint
0.40LOEUF
pLI 0.803
Z-score 3.67
OE 0.17 (0.090.40)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint
3.52Z-score
OE missense 0.53 (0.480.59)
242 obs / 452.6 exp
Constrained

Highly missense-constrained (top ~0.1%)

Observed / Expected Ratios
LoF OE0.17 (0.090.40)
00.351.4
Missense OE0.53 (0.480.59)
00.61.4
Synonymous OE0.94
01.21.6
LoF obs/exp: 4 / 23.0Missense obs/exp: 242 / 452.6Syn Z: 0.60
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
limitedADARB1-related microcephaly, intellectual disability, and seizuresOTHERAR

Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.

DN
0.4388th %ile
GOF
0.3193th %ile
LOF
0.71top 10%

The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.

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

ADARB1 · 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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