Is CD3D p.Thr103= (c.309C>T) pathogenic?

CD3D p.Thr103= (c.309C>T) is classified Likely benign in CD3D (ClinVar, Multiple submitters, 3 submitters; last evaluated 2025-01-23). Ultra-rare (popmax 0.0267%, eas); Associated with immunodeficiency 19.

What condition is associated with CD3D p.Thr103= (c.309C>T)?

CD3D p.Thr103= (c.309C>T) is associated with immunodeficiency 19 (ClinVar).

How common is CD3D p.Thr103= (c.309C>T) in the general population?

CD3D p.Thr103= (c.309C>T) is ultra-rare (popmax 0.0267%, eas) (gnomAD).

CD3D p.Thr103=

Q: How is T-B+ severe combined immunodeficiency due to CD3delta/CD3epsilon/CD3zeta inherited?

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

c.309C>T · rs777386322 · VCV755525

Likely benign Multiple submitters

Classification

Likely benign

ClinVar

Review

Multiple submitters ★★☆☆

ClinVar · 3 submitters

gnomAD v4.1

Rare

ultra-rare (popmax 0.0267%, eas)

Conditions

immunodeficiency 19

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 -1	GERP 0.091
Overall
CADD	8.885	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0267% East Asian · 12/44,896 alleles

Filtering AF 0.0154% ClinGen BA1/BS1 input FAF95, joint · FAF99 0.0121%

Overall 0.00341% 55/1,613,718 alleles · ultra-rare

Ancestry group	Frequency	1 in
East Asiangrpmax	0.0267%	3,741
South Asian	0.0187%	5,357
Admixed American	0.00333%	29,987
European (non-Finnish)	0.00195%	51,298
Remaining individualsnot grpmax-eligible	0.0016%	62,476

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: CD3D
Protein: p.Thr103=
Coding: c.309C>T
MANE Select: NM_000732
dbSNP: rs777386322
Type: single nucleotide variant
Location: chr11:118339872 (GRCh38)
Gene constraint: LOEUF 1.325 · pLI <0.01 · ClinGen HI gene assoc. with recessive phenotype (gnomAD)
Structure: AlphaFold pLDDT 77.57 · 31 PDB
Residue 103: an α-helix

Full CD3D gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

immunodeficiency 19 — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

For T-B+ severe combined immunodeficiency due to CD3delta/CD3epsilon/CD3zeta (Orphanet):

Inheritance: Autosomal recessive
Onset: Infancy

Similar variants

CD3D c.274+5G>A Pathogenic/Likely pathogenic ★★ same condition
CD3D c.407-2A>G Likely pathogenic ★★ same condition
CD3D p.Arg68Ter Pathogenic ★★ same condition
CD3D p.Cys93Ter Pathogenic ★★ same condition
CD3D c.274+4C>T Uncertain significance ★★ same condition
CD3D c.450+6C>T Uncertain significance ★★ same condition
CD3D p.Ala119Asp Uncertain significance ★★ ⚠ same condition
CD3D p.Arg169Gln 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/cd3d-p-thr103 (accessed [today's date]).

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