Is STAT1 p.Tyr668Phe (c.2003A>T) pathogenic?

STAT1 p.Tyr668Phe (c.2003A>T) is classified Uncertain significance in STAT1 (ClinVar, Single submitter, 1 submitter; last evaluated 2024-10-14). AlphaMissense: likely benign (0.0904); Very rare (popmax 0.000424%, nfe); Associated with immunodeficiency 31B.

How common is STAT1 p.Tyr668Phe (c.2003A>T) in the general population?

STAT1 p.Tyr668Phe (c.2003A>T) is very rare (popmax 0.000424%, nfe) (gnomAD).

What do computational predictors say about STAT1 p.Tyr668Phe (c.2003A>T)?

AlphaMissense predicts likely benign (score 0.0904) — an in-silico prediction, not a clinical call.

STAT1 p.Tyr668Phe

Q: What condition is associated with STAT1 p.Tyr668Phe (c.2003A>T)?

STAT1 p.Tyr668Phe (c.2003A>T) is associated with immunodeficiency 31B, autoimmune enteropathy and endocrinopathy - susceptibility to chronic infections syndrome, Mendelian susceptibility to mycobacterial diseases due to partial STAT1 deficiency (ClinVar).

Q: How is Susceptibility to viral and mycobacterial infections due to STAT1 deficiency inherited?

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

c.2003A>T · rs771679419 · VCV1378098

Uncertain significance Single submitter

Classification

Uncertain significance

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

AlphaMissense

likely benign

0.0904 · ACMG-weighted

gnomAD v4.1

Rare

very rare (popmax 0.000424%, nfe)

Missense predictors

1/3 damaging

AlphaMissense, REVEL, SaProt

Conditions

immunodeficiency 31B

Computational evidence

Protein change
AlphaMissense	0.0904	likely benign
REVEL	0.829	moderately pathogenic-leaning
SaProt	LLR -7.70	tolerated
⇒ REVEL calls this damaging; AlphaMissense and SaProt do not.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP 6.2	GERP 1.9, phastCons 1
Regional constraint	o/e 0.42	unconstrained · MANE · 15 kb · p 1.6e-32 · regional, not allelic
Overall
CADD	25.0	PHRED · no single calibrated threshold — expert panels disagree

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

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.000424% European (non-Finnish) · 5/1,180,038 alleles

Filtering AF 0.000124% ClinGen BA1/BS1 input FAF95, joint · FAF99 9e-05%

Overall 0.000372% 6/1,614,098 alleles · very rare exomes 4/1,461,874 · genomes 2/152,224 · joint denominator

Ancestry group	Frequency	1 in
Remaining individualsnot grpmax-eligible	0.0016%	62,488
European (non-Finnish)grpmax	0.000424%	236,008

Remaining individuals shows a higher raw frequency than the grpmax group above it. gnomAD excludes bottlenecked groups — Finnish, Ashkenazi Jewish, Amish and “Remaining individuals” — from grpmax, because founder effects make their frequencies unrepresentative for filtering. The table is sorted by frequency, so an excluded group can sit above the grpmax row.

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: STAT1
Protein: p.Tyr668Phe
Coding: c.2003A>T
MANE Select: NM_007315
dbSNP: rs771679419
Type: single nucleotide variant
Location: chr2:190976896 (GRCh38)
Gene constraint: LOEUF 0.271 · pLI 1.00 · ClinGen HI 0/3 (gnomAD)
Structure: AlphaFold pLDDT 87.78 · 10 PDB
Residue 668: a turn; the sh2 domain

Full STAT1 gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

immunodeficiency 31B — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: autoimmune enteropathy and endocrinopathy - susceptibility to chronic infections syndrome Mendelian susceptibility to mycobacterial diseases due to partial STAT1 deficiency

For Susceptibility to viral and mycobacterial infections due to STAT1 deficiency (Orphanet):

Inheritance: Autosomal recessive

Similar variants

STAT1 p.Ala267Val Pathogenic ★★ ⚠ same condition
STAT1 p.Arg274Gln Pathogenic ★★ ⚠ same condition
STAT1 p.Arg274Gly Pathogenic/Likely pathogenic ★★ same condition
STAT1 p.Arg274Trp Pathogenic ★★ same condition
STAT1 p.Asp171Asn Likely pathogenic ★★ ⚠ same condition
STAT1 p.Asp292Glu Likely pathogenic ★★ ⚠ same condition
STAT1 p.Cys324Arg Likely pathogenic ★★ same condition
STAT1 p.Gln271Pro Pathogenic/Likely 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/stat1-p-tyr668phe (accessed [today's date]).

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