# NM_000733.4(CD3E):c.55G>A (p.Val19Ile)

https://sugi.bio/variant/cd3e-p-val19ile

## Summary

**CD3E p.Val19Ile (c.55G>A)** is classified **Conflicting classifications of pathogenicity** in CD3E (ClinVar, Conflicting submitters, 3 submitters; last evaluated 2024-04-24). AlphaMissense: likely benign (0.0861); Rare (popmax 0.149%, mid); Associated with immunodeficiency 18.

**At a glance:** Conflicting classifications of pathogenicity · review: Conflicting submitters · rsID rs143630318 · 3 submitters · 1 linked condition · AlphaMissense likely benign · rare (popmax 0.149%, mid)

## For patients & families {#patients}

This is a change in the CD3E gene that is of uncertain or conflicting significance (submitters disagree on it), submitted by 3 submitters, and is linked to immunodeficiency 18.

*Reference information, not medical advice, and not a prediction for any individual. A genetic counselor or clinician can interpret what it means for you and your family.*

|  |  |
| --- | --- |
| Typical inheritance (of this condition) | Autosomal recessive |
| Age of onset (of this condition) | Infancy |
| Diagnostic panels | CD3E is a diagnostic-grade gene on 2 Genomics England panels |

**Commonly reported features of T-B+ severe combined immunodeficiency due to CD3delta/CD3epsilon/CD3zeta** (across patients with this condition; presentation varies — frequencies from Orphanet):

- Recurrent infections — Very frequent (99-80%)
- Lymphopenia — Frequent (79-30%)
- Fever — Frequent (79-30%)
- Decreased circulating total IgA — Frequent (79-30%)
- Decreased circulating IgG level — Frequent (79-30%)
- Failure to thrive secondary to recurrent infections — Frequent (79-30%)
- Decreased lymphocyte proliferation in response to mitogen — Frequent (79-30%)
- Decreased proportion of CD3-positive T cells — Frequent (79-30%)

**Support & next steps:** [Condition overview & support (NIH GARD)](https://rarediseases.info.nih.gov/diseases/0018295/index) · [Find a genetic counselor (NSGC)](https://findageneticcounselor.nsgc.org/).

## Identity {#identity}

| Field | Value |
| --- | --- |
| Gene | [CD3E](https://sugi.bio/atlas/gene/CD3E/) |
| Protein change (HGVS p.) | p.Val19Ile |
| Coding change (HGVS c.) | c.55G>A |
| MANE Select transcript | [NM_000733](https://www.ncbi.nlm.nih.gov/nuccore/NM_000733) |
| dbSNP | [rs143630318](https://www.ncbi.nlm.nih.gov/snp/rs143630318/) |
| Variant type | single nucleotide variant |
| Location | chr11:118307293-118307293 (GRCh38) |
| ClinVar | [VCV426577](https://www.ncbi.nlm.nih.gov/clinvar/variation/426577/) |

**All HGVS expressions:** `LRG_38:g.7714G>A`, `LRG_38t1:c.55G>A`, `NC_000011.10:g.118307293G>A`, `NC_000011.9:g.118178008G>A`, `NG_007383.1:g.7714G>A`, `NM_000733.4:c.55G>A`

## Computational & population evidence {#evidence}

**Concordance:** Mixed / partial computational evidence (see below).

- AlphaMissense **likely benign** (0.0861)
- REVEL 0.016 (strongly benign-leaning) — agrees with AlphaMissense
- SaProt LLR -7.922 (tolerated) — agrees with AlphaMissense
- → **In-silico consensus:** AlphaMissense, REVEL and SaProt all call this tolerated
- SpliceAI predicts **donor loss** (Δ 0.20) — a splice-altering prediction the current classification does not reflect
- Conservation: phyloP 0.974, GERP -3.85 — weakly conserved position
- CADD: **PHRED 6.531**. No single ClinGen-calibrated threshold exists and the expert panels that use CADD disagree — GUCY2D/AIPL1 require ≥ 20.0 for an untranslated-region variant, ABCA4 ≥ 28.1 for a synonymous or indel variant, the Pulmonary Hypertension panel imports Pejaver 2022's missense-calibrated numbers, and the Antibody Deficiencies panel declines CADD entirely for PIK3CD. CADD v1.7 also incorporates Zoonomia phyloP, so it partly re-expresses the conservation above. *Descriptive; no threshold applied.*
- Regional missense constraint: **o/e 0.88** across the covering region of the MANE Select transcript (118,304,953–118,315,539), spanning 10,586 bp. Chi-square p 0.052. Describes the region, not this allele; gnomAD v4.1.1's own constrained determination. *Descriptive; no ACMG code applied.*
- SpliceAI deltas (raw): acceptor loss **0.13**, donor loss **0.20**, acceptor gain **0.00**, donor gain **0.00**. Largest is donor loss, 15 bp away.
- SpliceAI deltas (masked): acceptor loss **0.00**, donor loss **0.00**, acceptor gain **0.00**, donor gain **0.00**.
  Masked SpliceAI — what Ensembl VEP and the Broad lookup serve by default — is below the reporting threshold here, so those tools show **no splice signal** for this allele. Masking zeroes a loss scored against a position that is not an annotated splice site, and a gain that merely strengthens an existing one, so the raw score above is describing a cryptic site rather than the site the variant sits on. *No ACMG code is assigned either way.*
- Population frequency (gnomAD v4.1): grpmax **0.149%** (mid) · FAF95 0.0775% · FAF99 0.0579% · 9/6,050 in the highest group · 38/1,606,640 alleles overall — rare (popmax 0.149%, mid).

| Ancestry group | Allele frequency | 1 in |
| --- | --- | --- |
| Middle Eastern (grpmax) | 0.149% | 672 |
| Remaining individuals (not grpmax-eligible) | 0.00803% | 12,457 |
| African / African-American | 0.00267% | 37,448 |
| South Asian | 0.00221% | 45,349 |
| European (non-Finnish) | 0.0017% | 58,714 |

*Computational predictors are not independent (ClinGen Variant Classification guidance): AlphaMissense (Cheng et al. 2023) carries the ACMG weight for missense and conservation (phyloP/GERP/phastCons) for non-missense; REVEL (Pejaver-2022 calibrated strength bands) and SaProt (Su et al. 2023, structure-aware, ClinVar-independent protein language model, raw LLR) are shown as orthogonal agreement signals, not additive. For frequency, the gnomAD v4.1 grpmax filtering allele frequency (FAF95) is ClinGen's designated BA1/BS1 input (gnomAD v4 guidance v3.0, June 2025); BA1/BS1 thresholds are disease-specific, not a blanket 5%. Predictions, not a clinical determination.*

## Gene constraint & dosage {#gene-context}

**CD3E** population constraint: LOEUF 0.659, pLI 0.46931, missense-Z 0.88647; ClinGen dosage — haploinsufficiency 30, triplosensitivity 0 (0–3 scale). *Lower LOEUF and higher pLI indicate a gene that tolerates loss-of-function poorly; ClinGen dosage is the curated haploinsufficiency call.*

Curated gene–disease validity (ClinGen):

- **immunodeficiency 18** — Definitive (AR)

## Protein context {#protein}


AlphaFold model confidence (whole protein): pLDDT 73.56, 30% of residues very-high.

**44 experimental structure(s)** (PDB): [1A81](https://www.rcsb.org/structure/1A81), [1SY6](https://www.rcsb.org/structure/1SY6), [1XIW](https://www.rcsb.org/structure/1XIW), [2ROL](https://www.rcsb.org/structure/2ROL), [5QU2](https://www.rcsb.org/structure/5QU2), [6JXR](https://www.rcsb.org/structure/6JXR).

## What this gene does {#gene-function}

*Describes the biological roles of CD3E (the gene this variant disrupts) — not effects measured for this specific variant. A damaging variant is expected to affect these functions and pathways; the degree depends on the variant.*

**How this variant is thought to act:** CD3E's established molecular role includes transmembrane signaling receptor activity.


### Pathways affected {#pathways}

CD3E participates in **6 Reactome pathways** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| [Co-inhibition by PD-1](https://reactome.org/content/detail/R-HSA-389948) | curated |
| [Downstream TCR signaling](https://reactome.org/content/detail/R-HSA-202424) | curated |
| [Generation of second messenger molecules](https://reactome.org/content/detail/R-HSA-202433) | curated |
| [Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cell](https://reactome.org/content/detail/R-HSA-198933) | curated |
| [Phosphorylation of CD3 and TCR zeta chains](https://reactome.org/content/detail/R-HSA-202427) | curated |
| [Translocation of ZAP-70 to Immunological synapse](https://reactome.org/content/detail/R-HSA-202430) | curated |

### Molecular function & processes (GO — experimentally supported) {#go}

**Molecular function:** transmembrane signaling receptor activity, SH3 domain binding, protein-macromolecule adaptor activity, identical protein binding.

**Biological process:** positive regulation of gene expression, negative regulation of gene expression, positive regulation of T cell proliferation, T cell receptor signaling pathway.

## Clinical significance {#significance}

**Conflicting classifications of pathogenicity** — review status Conflicting submitters *(criteria provided, conflicting classifications)*, last evaluated 2024-04-24.

**Submitter consensus:** conflicting (2 Likely benign, 1 Uncertain significance).

**Submission history:** 3 submissions (2018–2024); classifications have differed over time.

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| Labcorp Genetics (formerly Invitae), Labcorp | Uncertain significance | criteria provided, single submitter | clinical testing | 2022-10-05 |
| GeneDx | Likely benign | criteria provided, single submitter | clinical testing | 2018-07-18 |
| Blueprint Genetics | Likely benign | criteria provided, single submitter | clinical testing | 2024-04-24 |

## Associated conditions {#conditions}

[immunodeficiency 18](https://sugi.bio/atlas/disease/immunodeficiency-18/).

**Reported phenotype names (ClinVar):** Immunodeficiency 18, not provided, not specified, AllHighlyPenetrant, CD3epsilon deficiency, CD3-EPSILON DEFICIENCY, none provided.

## Similar variants {#similar}

Related CD3E variant pages (same residue, condition, or type): [CD3E c.103+1G>A](/variant/cd3e-c-103-plus-1g-a), [CD3E c.49+1G>C](/variant/cd3e-c-49-plus-1g-c), [CD3E p.Tyr96Ter](/variant/cd3e-p-tyr96ter), [CD3E c.520+5G>A](/variant/cd3e-c-520-plus-5g-a), [CD3E p.Arg192Gln](/variant/cd3e-p-arg192gln), [CD3E p.Arg206His](/variant/cd3e-p-arg206his), [CD3E p.Asn25Asp](/variant/cd3e-p-asn25asp), [CD3E p.Asn74Thr](/variant/cd3e-p-asn74thr).

### Data sources & attribution {#sources}

ClinVar (NCBI — public domain, built 2026-10-11); gnomAD v4.1 (Broad Institute, built 2026-10-06); AlphaMissense (Cheng et al. 2023, © Google DeepMind — CC BY 4.0, built 2026-01-27); REVEL (Ioannidis et al. 2016 — ODbL, built 2026-07-13); SaProt (Su et al. 2023 — MIT, built 2026-07-14); SpliceAI (Illumina — free for non-commercial use, built 2026-10-13); CADD (Rentzsch et al. 2019, University of Washington — free for non-commercial use, built 2026-10-10); Conservation (phyloP/phastCons/GERP) (UCSC hg38 470-way mammal (Hiller Lab) + Ensembl Compara, built 2026-07-12); gnomAD Non-coding Constraint (Gnocchi) (Chen et al. 2024, Broad Institute — CC0, built 2026-10-11); gnomAD Regional Missense Constraint (Broad Institute — CC0, built 2026-10-13); Pangolin (Zeng & Li 2022 — CC BY 4.0, built 2026-10-11); Repeat regions (UCSC — RepeatMasker, TRF, segmental duplications, built 2026-10-11); ClinGen (ClinGen, built 2026-09-22); UniProt (CC BY 4.0); Reactome / GO (CC BY 4.0, built 2026-09-23); MaveDB (per-record license, built 2026-10-11); CIViC (CC0, built 2026-09-22); Orphanet (Orphanet, built 2026-06-12)

*Primary record: NCBI ClinVar (variation 426577). Classifications reflect these databases as of the page's build date and may change. Free reference use — not medical advice; consult the primary submitters and a clinician.*