MYO3A

Chr 10ADAR

myosin IIIA

Also known as: DFNA90, DFNB30

This actin-dependent motor protein with kinase activity is essential for cochlear hair bundle development and hearing, transporting actin regulatory factors to stereocilia tips and contributing to the characteristic staircase architecture of auditory hair bundles. Mutations cause nonsyndromic hearing loss with both autosomal dominant and autosomal recessive inheritance patterns. The gene shows very low constraint against loss-of-function variants and is highly expressed in the retina and cochlea.

GeneReviewsOMIMResearchSummary from RefSeq, OMIM, UniProt
MultiplemechanismAD/ARLOEUF 1.042 OMIM phenotypes
Clinical SummaryMYO3A
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Gene-Disease Validity (ClinGen)
nonsyndromic genetic hearing loss · ARDefinitive

Definitive — sufficient evidence for diagnostic panels

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
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ClinVar Variants
38 unique Pathogenic / Likely Pathogenic· 327 VUS of 500 total submissions
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GeneReview available — MYO3A
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
1.04LOEUF
pLI 0.000
Z-score 1.23
OE 0.86 (0.711.04)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.13Z-score
OE missense 1.01 (0.961.07)
841 obs / 830.3 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.86 (0.711.04)
00.351.4
Missense OE1.01 (0.961.07)
00.61.4
Synonymous OE1.07
01.21.6
LoF obs/exp: 76 / 88.5Missense obs/exp: 841 / 830.3Syn Z: -0.95
DN
0.7130th %ile
GOF
0.73top 25%
LOF
0.3454th %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

500 submitted variants in ClinVar

Classification Summary

Pathogenic21
Likely Pathogenic17
VUS327
Likely Benign102
Benign7
Conflicting11
21
Pathogenic
17
Likely Pathogenic
327
VUS
102
Likely Benign
7
Benign
11
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
14
1
6
0
21
Likely Pathogenic
17
0
0
0
17
VUS
8
296
18
5
327
Likely Benign
0
1
46
55
102
Benign
0
0
5
2
7
Conflicting
11
Total392987562485

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

View in ClinVar →

Protein Context — Lollipop Plot

MYO3A · 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 →