Is EDA p.Gln256Ter (c.766C>T) pathogenic?

EDA p.Gln256Ter (c.766C>T) is classified Pathogenic in EDA (ClinVar, Multiple submitters, 2 submitters; last evaluated 2019-03-18). Absent from gnomAD v4.1; Associated with X-linked hypohidrotic ectodermal dysplasia.

What condition is associated with EDA p.Gln256Ter (c.766C>T)?

EDA p.Gln256Ter (c.766C>T) is associated with X-linked hypohidrotic ectodermal dysplasia (ClinVar).

How common is EDA p.Gln256Ter (c.766C>T) in the general population?

EDA p.Gln256Ter (c.766C>T) is absent from gnomAD v4.1 (gnomAD).

How is Hypohidrotic ectodermal dysplasia inherited?

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

EDA p.Gln256Ter

c.766C>T · rs727504417 · VCV177947

Pathogenic Multiple submitters

Classification

Pathogenic

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 2 submitters

Consequence

nonsense (stop-gain)

predicted LoF

gnomAD v4.1

Not reported

no allele count reported in gnomAD v4.1 (AN 1,205,864)

Conditions

X-linked hypohidrotic ectodermal dysplasia

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation/SpliceAI carries the signal.
Consequence	nonsense (stop-gain)	predicted loss-of-function in a haploinsufficient gene (ClinGen)
NMD	predicted	premature termination codon in exon 6 of 8
Splicing
SpliceAI	Δ0.38	donor loss · deltas
Pangolin	Δ0.34	loss · gain 0.00 · agrees with SpliceAI · independent
Constraint at this position
Conservation	phyloP 7.5	GERP 4.8, phastCons 1
Overall
CADD	40.0	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 1,205,864). 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: EDA
Protein: p.Gln256Ter
Coding: c.766C>T
MANE Select: NM_001399
dbSNP: rs727504417
Type: single nucleotide variant
Location: chrX:70030493 (GRCh38)
Structure: AlphaFold pLDDT 70.59 · 3 PDB
Residue 256: the thd domain

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

Disease context

X-linked hypohidrotic ectodermal dysplasia — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For Hypohidrotic ectodermal dysplasia (Orphanet):

Inheritance: Autosomal dominant, Autosomal recessive, X-linked recessive
Onset: Infancy, Neonatal
Prevalence: 1-9 / 100 000 (Europe)

Similar variants

EDA c.526+5G>T Likely pathogenic ★★ same condition
EDA c.527-2A>G Pathogenic/Likely pathogenic ★★ same condition
EDA c.706+1G>A Pathogenic/Likely pathogenic ★★ same condition
EDA c.707-13T>G Pathogenic ★★ same condition
EDA c.742-2A>G Pathogenic/Likely pathogenic ★★ same condition
EDA c.924+1G>T Likely pathogenic ★★ same condition
EDA p.Ala349Ser Likely pathogenic ★★ same condition
EDA p.Ala349Thr 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/eda-p-gln256ter (accessed [today's date]).

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