Is STRADA p.Val318= (c.954G>A) pathogenic?

STRADA p.Val318= (c.954G>A) is classified Likely benign in STRADA (ClinVar, Single submitter, 1 submitter; last evaluated 2025-01-27). Very rare (popmax 0.000339%, nfe); Associated with polyhydramnios, megalencephaly, and symptomatic epilepsy.

What condition is associated with STRADA p.Val318= (c.954G>A)?

STRADA p.Val318= (c.954G>A) is associated with polyhydramnios, megalencephaly, and symptomatic epilepsy (ClinVar).

How common is STRADA p.Val318= (c.954G>A) in the general population?

STRADA p.Val318= (c.954G>A) is very rare (popmax 0.000339%, nfe) (gnomAD).

STRADA p.Val318=

Q: How is Polyhydramnios-megalencephaly-symptomatic epilepsy syndrome inherited?

Typically Autosomal recessive (Orphanet). A genetic counselor can assess individual risk for a family.

c.954G>A · rs767576976 · VCV1640708

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.000339%, nfe)

Conditions

polyhydramnios, megalencephaly, and symptomatic epilepsy

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -7.4	GERP -3.6
Overall
CADD	0.15	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000339% European (non-Finnish) · 4/1,179,660 alleles

Filtering AF 7.9e-05% ClinGen BA1/BS1 input FAF95, joint · FAF99 5.4e-05%

Overall 0.000248% 4/1,612,914 alleles · very rare exomes 4/1,460,714 · genomes 0/152,200 · joint denominator

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: STRADA
Protein: p.Val318=
Coding: c.954G>A
MANE Select: NM_001003787
dbSNP: rs767576976
Type: single nucleotide variant
Location: chr17:63704487 (GRCh38)
Gene constraint: LOEUF 0.649 · pLI <0.01 (gnomAD)
Structure: AlphaFold pLDDT 80.46 · 4 PDB
Residue 318: the protein kinase domain; the 'disordered' region

Full STRADA gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

polyhydramnios, megalencephaly, and symptomatic epilepsy — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Polyhydramnios-megalencephaly-symptomatic epilepsy syndrome (Orphanet):

Inheritance: Autosomal recessive
Onset: Antenatal, Infancy, Neonatal

Similar variants

STRADA p.Val318Ala Uncertain significance ★ ⚠ same residue
STRADA p.Val318_Ser324del Uncertain significance ★ same residue
STRADA c.36+1G>A Likely pathogenic ★★ same condition
STRADA c.37-1G>C Likely pathogenic ★★ same condition
STRADA p.Arg228Ter Pathogenic ★★ same condition
STRADA p.Ala45Val Uncertain significance ★★ ⚠ same condition
STRADA p.Arg100Gln Uncertain significance ★★ ⚠ same condition
STRADA p.Arg13Gln Uncertain significance ★★ same condition

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/strada-p-val318 (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown