Is ARX p.Trp375Ter (c.1125G>A) pathogenic?

ARX p.Trp375Ter (c.1125G>A) is classified Pathogenic in ARX (ClinVar, Single submitter, 1 submitter; last evaluated 2020-11-04). Absent from gnomAD v4.1; Associated with developmental and epileptic encephalopathy, 1.

What condition is associated with ARX p.Trp375Ter (c.1125G>A)?

ARX p.Trp375Ter (c.1125G>A) is associated with developmental and epileptic encephalopathy, 1, intellectual disability, X-linked, with or without seizures, ARX-related (ClinVar).

How common is ARX p.Trp375Ter (c.1125G>A) in the general population?

ARX p.Trp375Ter (c.1125G>A) 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.

ARX p.Trp375Ter

c.1125G>A · rs2147320638 · VCV1374869

Pathogenic Single submitter

Classification

Pathogenic

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Not reported

no allele count reported in gnomAD v4.1 (AN 1,161,569)

Conditions

developmental and epileptic encephalopathy, 1

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function in a haploinsufficient gene (ClinGen)
NMD	predicted	premature termination codon in exon 4 of 5
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 5.9	GERP 2.1, phastCons 1
Overall
CADD	38.0	PHRED · no single calibrated threshold — expert panels disagree

Predicted loss-of-function is descriptive, not an applied PVS1 code.

Population frequency

gnomAD v4.1 · exomes + genomes

No allele count reported in gnomAD v4.1 (AN 1,161,569). 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.Trp375Ter
Coding: c.1125G>A
MANE Select: NM_139058
dbSNP: rs2147320638
Type: single nucleotide variant
Location: chrX:25007434 (GRCh38)
Structure: AlphaFold pLDDT 56.51
Residue 375: a DNA-binding region

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.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
ARX p.Pro353Leu 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-trp375ter (accessed [today's date]).

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