DNAJB3
Chr 2DnaJ heat shock protein family (Hsp40) member B3
Also known as: HCG3
DNAJB3 encodes a co-chaperone protein that assists heat shock protein 70 (Hsp70) in protein folding, particularly in male germ cells during haploid stages of development. Mutations cause autosomal recessive spinal muscular atrophy with congenital bone fractures, a severe neuromuscular disorder with onset in infancy or early childhood. The condition affects both the motor neuron system and bone development, leading to muscle weakness and increased fracture susceptibility.
Population Genetics & Constraint
Constraint data not available from gnomAD.
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.
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
DNAJB3 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
No active trials found for this gene.
Search ClinicalTrials.gov →External Resources
Links to major genomics databases and tools