SYN1 p.Ala637=
c.1911C>G · VCV4950310
Likely benign
Single submitter
Classification
Likely benign
ClinVar
Review
Single submitter ★☆☆☆
ClinVar · 1 submitter
gnomAD v4.1
Absent
absent from gnomAD v4.1
Computational evidence
| Protein change | ||
| Missense predictors do not apply to this variant type; conservation carries the signal. | ||
| Splicing | ||
| SpliceAI | <0.2 | no splice effect predicted · four deltas, not one · how we know |
|---|---|---|
| Constraint at this position | ||
| Conservation | phyloP 0.47 | phastCons 0.99 |
| Overall | ||
| CADD | 9.883 | PHRED · no single calibrated threshold — expert panels disagree |
Population frequency
gnomAD v4.1 · exomes + genomes
Absent from gnomAD v4.1. Not observed in any sequenced alleles — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.
Variant & gene context
- Gene
- SYN1
- Protein
- p.Ala637=
- Coding
- c.1911C>G
- MANE Select
- NM_006950
- Type
- single nucleotide variant
- Location
- chrX:47574073 (GRCh38)
- Structure
- AlphaFold pLDDT 69.86
- Residue 637
- the 'disordered' region; a UniProt-annotated variant site (in xlid50; affects excitatory and inhibitory synaptic transmission leading to neuronal hyperexcitability; fails to rescue defective synaptic vesicle exocytosis in syn1-knockout mouse neurons; results in severely decreased phosphorylation by camk2 and mapk1; results in delayed axon elongation when tested in syn1-knockout mouse neurons; severely reduced interaction with syn2; has no effect on protein targeting to presynapse); the 'd; pro-rich linker' region
Similar variants
- SYN1 c.528-2A>T Pathogenic/Likely pathogenic ★★ same type
- SYN1 c.838-2A>G Likely pathogenic ★★ same type
- SYN1 p.Arg234Ter Pathogenic ★★ same type
- SYN1 p.Arg420Gln Likely pathogenic ★★ ⚠ same type
- SYN1 p.Arg422Ter Pathogenic ★★ same type
- SYN1 p.Gln249Ter Pathogenic/Likely pathogenic ★★ same type
- SYN1 p.Gln483Ter Pathogenic ★★ same type
- SYN1 p.Gln555Ter Pathogenic ★★ same type
Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →
Cite Sugi Variant
Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/syn1-p-ala637 (accessed [today's date]).
Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown