SYN1
Chr XX-linkedsynapsin I
Also known as: EPILX, EPILX1, MRX50, SYN1a, SYN1b, SYNI
Synapsin I is a neuronal phosphoprotein that coats synaptic vesicles and regulates neurotransmitter release at presynaptic terminals, while also controlling axon outgrowth and synaptogenesis. Mutations cause X-linked epilepsy with variable learning disabilities and behavior disorders, as well as X-linked intellectual developmental disorder. Disease predominantly results from loss-of-function mutations, consistent with the gene's high intolerance to such variants.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly LoF-intolerant (top ~10% of genes)
Moderately missense-constrained (top ~2.5%)
The highest-scoring mechanism for this gene is loss-of-function (haploinsufficiency).
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
SYN1 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
External Resources
Links to major genomics databases and tools