VWA1

Chr 1AR

von Willebrand factor A domain containing 1

Also known as: HMNMYO, HMNR7, WARP

VWA1 encodes a von Willebrand factor A domain-containing protein that promotes extracellular matrix assembly and is involved in skeletal muscle organization and neuromuscular junction formation. Mutations cause autosomal recessive distal hereditary motor neuronopathy type 7, which affects peripheral motor neurons and results in distal muscle weakness. The gene shows tolerance to loss-of-function variants (LOEUF 1.066), consistent with its recessive inheritance pattern.

OMIMResearchSummary from RefSeq, OMIM, UniProt
MultiplemechanismARLOEUF 1.071 OMIM phenotype
Clinical SummaryVWA1
Population Constraint (gnomAD)
Low constraint (pLI 0.01) — 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
1.07LOEUF
pLI 0.005
Z-score 1.43
OE 0.51 (0.261.07)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint
-0.15Z-score
OE missense 1.03 (0.921.15)
219 obs / 212.9 exp
Tolerant

Tolerant to missense variation

Observed / Expected Ratios
LoF OE0.51 (0.261.07)
00.351.4
Missense OE1.03 (0.921.15)
00.61.4
Synonymous OE0.96
01.21.6
LoF obs/exp: 5 / 9.9Missense obs/exp: 219 / 212.9Syn Z: 0.32
DN
0.7326th %ile
GOF
0.83top 10%
LOF
0.2582th %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

VWA1 · 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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