ACTN2

Chr 1AD

actinin alpha 2

Also known as: CMD1AA, CMH23, CMYO8, CMYP8, MPD6, MYOCOZ

Alpha-actinin-2 is an F-actin cross-linking protein that anchors actin filaments to the Z-disc in skeletal and cardiac muscle. Mutations cause autosomal dominant cardiomyopathies (dilated and hypertrophic, with or without left ventricular noncompaction), congenital myopathy, and adult-onset distal myopathy. The gene is extremely intolerant to loss-of-function variants (pLI >0.99), indicating that complete loss of function is likely incompatible with normal development.

OMIMResearchSummary from RefSeq, OMIM, UniProt
MultiplemechanismADLOEUF 0.244 OMIM phenotypes
Clinical SummaryACTN2
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Gene-Disease Validity (ClinGen)
ACTN2-related cardiac and skeletal myopathy · ADDefinitive

Definitive — sufficient evidence for diagnostic panels

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
0.24LOEUF
pLI 1.000
Z-score 5.73
OE 0.12 (0.070.24)
Highly constrained

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

Missense Constraint
1.29Z-score
OE missense 0.84 (0.780.91)
446 obs / 529.7 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.12 (0.070.24)
00.351.4
Missense OE0.84 (0.780.91)
00.61.4
Synonymous OE0.97
01.21.6
LoF obs/exp: 6 / 49.6Missense obs/exp: 446 / 529.7Syn Z: 0.33
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
definitiveACTN2-related cardiac and skeletal myopathyOTHERAD
DN
0.6164th %ile
GOF
0.78top 25%
LOF
0.4233th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function and loss-of-function). 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
LOFLOEUF 0.24

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. Mechanism ranking also informed by gnomAD constraint, ClinVar, and ClinGen data.

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

ACTN2 · 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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Full-Text Mentions
NLP-detected gene mentions in article bodies · via PubTator3
PubTator3
Top 5 full-text resultsSearch PubTator3 ↗