Is ARX p.Ala523Val (c.1568C>T) pathogenic?

ARX p.Ala523Val (c.1568C>T) is classified Uncertain significance in ARX (ClinVar, Multiple submitters, 2 submitters; last evaluated 2025-02-07). AlphaMissense: likely benign (0.1167); Absent from gnomAD v4.1; Associated with developmental and epileptic encephalopathy, 1.

What condition is associated with ARX p.Ala523Val (c.1568C>T)?

ARX p.Ala523Val (c.1568C>T) is associated with developmental and epileptic encephalopathy, 1, intellectual disability, X-linked, with or without seizures, ARX-related (ClinVar).

How common is ARX p.Ala523Val (c.1568C>T) in the general population?

ARX p.Ala523Val (c.1568C>T) is absent from gnomAD v4.1 (gnomAD).

How is Infantile epileptic spasms syndrome inherited?

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

What do computational predictors say about ARX p.Ala523Val (c.1568C>T)?

AlphaMissense predicts likely benign (score 0.1167) — an in-silico prediction, not a clinical call.

ARX p.Ala523Val

c.1568C>T · rs1315081166 · VCV2943591

Uncertain significance Multiple submitters

Classification

Uncertain significance

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

AlphaMissense

likely benign

0.1167 · ACMG-weighted

gnomAD v4.1

Not reported

no allele count reported in gnomAD v4.1 (AN 1,171,221)

Missense predictors

0/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

developmental and epileptic encephalopathy, 1

Computational evidence

Protein change
AlphaMissense	0.1167	likely benign
REVEL	0.203	benign-leaning
SaProt	LLR -6.87	tolerated
⇒ AlphaMissense, REVEL and SaProt all call this tolerated.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 9.5	GERP -0.19, phastCons 1
Regional constraint	o/e 0.71	unconstrained · MANE · 2,715 bp · p 0.00019 · regional, not allelic
Overall
CADD	23.6	PHRED · no single calibrated threshold — expert panels disagree

ClinVar classifies this uncertain; the computational predictors unanimously lean tolerated — a triage signal, not a reclassification

AlphaMissense carries the ACMG weight for missense; REVEL and SaProt are independent agreement signals.

Population frequency

gnomAD v4.1 · exomes + genomes

No allele count reported in gnomAD v4.1 (AN 1,171,221). This is missing data, not an absence: the variant may or may not be present in gnomAD. Rarity (ACMG PM2) and BA1/BS1 cannot be assessed for it.

Variant & gene context

Gene: ARX
Protein: p.Ala523Val
Coding: c.1568C>T
MANE Select: NM_139058
dbSNP: rs1315081166
Type: single nucleotide variant
Location: chrX:25004791 (GRCh38)
Structure: AlphaFold pLDDT 56.51

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

Disease context

developmental and epileptic encephalopathy, 1 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: intellectual disability, X-linked, with or without seizures, ARX-related

For Infantile epileptic spasms syndrome (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive, X-linked dominant

Similar variants

ARX p.Ala523= Likely benign ★ same residue
ARX p.Arg330His Likely pathogenic ★★ same condition
ARX p.Arg332Gly Pathogenic/Likely pathogenic ★★ same condition
ARX p.Arg332His Pathogenic ★★ same condition
ARX p.Arg371Gln Likely pathogenic ★★ same condition
ARX p.Arg371Ter Pathogenic ★★ same condition
ARX p.Arg384Cys Pathogenic/Likely pathogenic ★★ same condition
ARX p.Glu294Ter Pathogenic ★★ 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/arx-p-ala523val (accessed [today's date]).

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