# NM_005419.4(STAT2):c.1466C>A (p.Pro489His)

https://sugi.bio/variant/stat2-p-pro489his

## Summary

**STAT2 p.Pro489His (c.1466C>A)** is classified **Uncertain significance** in STAT2 (ClinVar, Multiple submitters, 3 submitters; last evaluated 2026-02-12). AlphaMissense: likely benign (0.2312); Ultra-rare (popmax 0.0165%, mid); Associated with primary immunodeficiency with post-measles-mumps-rubella vaccine viral infection.

**At a glance:** Uncertain significance · review: Multiple submitters · rsID rs138681270 · 3 submitters · 1 linked condition · AlphaMissense likely benign · ultra-rare (popmax 0.0165%, mid)

## For patients & families {#patients}

This is a change in the STAT2 gene that is currently of uncertain significance — a definitive interpretation has not yet been established, submitted by 3 submitters, and is linked to primary immunodeficiency with post-measles-mumps-rubella vaccine viral infection.

*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 | STAT2 is a diagnostic-grade gene on 2 Genomics England panels |

**Support & next steps:** [Condition overview & support (NIH GARD)](https://rarediseases.info.nih.gov/diseases/0017711/index) · [Find a genetic counselor (NSGC)](https://findageneticcounselor.nsgc.org/).

## Identity {#identity}

| Field | Value |
| --- | --- |
| Gene | [STAT2](https://sugi.bio/atlas/gene/STAT2/) |
| Protein change (HGVS p.) | p.Pro489His |
| Coding change (HGVS c.) | c.1466C>A |
| MANE Select transcript | [NM_005419](https://www.ncbi.nlm.nih.gov/nuccore/NM_005419) |
| dbSNP | [rs138681270](https://www.ncbi.nlm.nih.gov/snp/rs138681270/) |
| Variant type | single nucleotide variant |
| Location | chr12:56349034-56349034 (GRCh38) |
| ClinVar | [VCV845773](https://www.ncbi.nlm.nih.gov/clinvar/variation/845773/) |

**All HGVS expressions:** `LRG_1329:g.16220C>A`, `LRG_1329t1:c.1466C>A`, `NC_000012.11:g.56742818G>T`, `NC_000012.12:g.56349034G>T`, `NG_046314.1:g.16220C>A`, `NM_005419.4:c.1466C>A`, `NM_198332.2:c.1454C>A`

## Computational & population evidence {#evidence}

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

- AlphaMissense **likely benign** (0.2312)
- REVEL 0.407 (indeterminate)
- SaProt LLR -12.836 (damaging) — differs from AlphaMissense
- → **In-silico consensus:** SaProt calls this damaging; AlphaMissense does not; REVEL is indeterminate
- Conservation: phyloP 5.807, GERP 0.695, phastCons 1 — highly conserved (differs from AlphaMissense)
- CADD: **PHRED 22.6**. 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 0.73** across the covering region of the MANE Select transcript (56,343,392–56,356,571), spanning 13,179 bp. Chi-square p 6.2e-18. Describes the region, not this allele; gnomAD v4.1.1's own constrained determination. *Descriptive; no ACMG code applied.*
- SpliceAI: **below the reporting threshold**. This position is scored for a different substitution (G>C, Δ0.24 acceptor loss), so this allele was evaluated and its deltas all fell under Δ0.2 — a prediction of no splicing effect for this allele, not a gap in our data. *No ACMG code assigned.*
- Population frequency (gnomAD v4.1): grpmax **0.0165%** (mid) · FAF95 0.00662% · FAF99 0.00533% · 1/6,060 in the highest group · 105/1,613,662 alleles overall — ultra-rare (popmax 0.0165%, mid).

| Ancestry group | Allele frequency | 1 in |
| --- | --- | --- |
| Middle Eastern (grpmax) | 0.0165% | 6,060 |
| Admixed American | 0.0133% | 7,495 |
| Remaining individuals (not grpmax-eligible) | 0.0096% | 10,416 |
| European (non-Finnish) | 0.00704% | 14,214 |
| East Asian | 0.00446% | 22,434 |
| South Asian | 0.0044% | 22,751 |
| African / African-American | 0.00133% | 75,042 |

*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}

**STAT2** population constraint: LOEUF 0.497, pLI 0.80697, missense-Z 3.6539. *Lower LOEUF and higher pLI indicate a gene that tolerates loss-of-function poorly; ClinGen dosage is the curated haploinsufficiency call.*

## Protein context {#protein}

Residue **489** lies in the 'mediates interaction with usp18' region; the 'interaction with heartland virus nss' region; an α-helix.

AlphaFold model confidence (whole protein): pLDDT 78.45, 49% of residues very-high.

**6 experimental structure(s)** (PDB): [2KA4](https://www.rcsb.org/structure/2KA4), [6UX2](https://www.rcsb.org/structure/6UX2), [6WCZ](https://www.rcsb.org/structure/6WCZ), [8T12](https://www.rcsb.org/structure/8T12), [8T13](https://www.rcsb.org/structure/8T13), [9ZFO](https://www.rcsb.org/structure/9ZFO).

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

*Describes the biological roles of STAT2 (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:** STAT2's established molecular role includes DNA-binding transcription factor activity, RNA polymerase II-specific. p.Pro489His falls in the mediates interaction with usp18 region. In Reactome, STAT2 is annotated in disease pathway(s) including **Dengue virus activates/modulates innate and adaptive immune responses**, **Evasion by RSV of host interferon responses**.

**Disease mechanism (Reactome):** STAT2 loss or alteration is curated in [Dengue virus activates/modulates innate and adaptive immune responses](https://reactome.org/content/detail/R-HSA-9920588), [Evasion by RSV of host interferon responses](https://reactome.org/content/detail/R-HSA-9833109), [Potential therapeutics for SARS](https://reactome.org/content/detail/R-HSA-9679191).

### Pathways affected {#pathways}

STAT2 participates in **7 Reactome pathways** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| ⚕ [Dengue virus activates/modulates innate and adaptive immune responses](https://reactome.org/content/detail/R-HSA-9920588) | curated |
| ⚕ [Evasion by RSV of host interferon responses](https://reactome.org/content/detail/R-HSA-9833109) | curated |
| ⚕ [Potential therapeutics for SARS](https://reactome.org/content/detail/R-HSA-9679191) | curated |
| ⚕ [SARS-CoV-2 activates/modulates innate and adaptive immune responses](https://reactome.org/content/detail/R-HSA-9705671) | curated |
| [Interferon alpha/beta signaling](https://reactome.org/content/detail/R-HSA-909733) | curated |
| [Interleukin-20 family signaling](https://reactome.org/content/detail/R-HSA-8854691) | curated |
| [Regulation of IFNA/IFNB signaling](https://reactome.org/content/detail/R-HSA-912694) | electronic |

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

**Molecular function:** DNA-binding transcription factor activity, RNA polymerase II-specific, DNA-binding transcription factor activity, identical protein binding, ubiquitin-like protein ligase binding.

**Biological process:** regulation of protein phosphorylation, regulation of transcription by RNA polymerase II, cell surface receptor signaling pathway via JAK-STAT, positive regulation of transcription by RNA polymerase II, defense response to virus, type I interferon-mediated signaling pathway.

## Clinical significance {#significance}

**Uncertain significance** — review status Multiple submitters *(criteria provided, multiple submitters, no conflicts)*, last evaluated 2026-02-12.

**Submitter consensus:** unanimous (3/3 Uncertain significance).

**Submission history:** 3 submissions (2022–2026); classifications have been stable.

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| Labcorp Genetics (formerly Invitae), Labcorp | Uncertain significance | criteria provided, single submitter | clinical testing | 2022-08-23 |
| Breakthrough Genomics, Breakthrough Genomics | Uncertain significance | criteria provided, single submitter | not provided |  |
| Women's Health and Genetics/Laboratory Corporation of America, LabCorp | Uncertain significance | criteria provided, single submitter | clinical testing | 2026-02-12 |

## Associated conditions {#conditions}

[primary immunodeficiency with post-measles-mumps-rubella vaccine viral infection](https://sugi.bio/atlas/disease/primary-immunodeficiency-with-post-measles-mumps-rubella-vaccine-viral-infection/).

**Reported phenotype names (ClinVar):** Primary immunodeficiency with post-measles-mumps-rubella vaccine viral infection, not provided, not specified, AllHighlyPenetrant, Immunodeficiency 44, none provided.

## Similar variants {#similar}

Related STAT2 variant pages (same residue, condition, or type): [STAT2 p.Pro489Arg](/variant/stat2-p-pro489arg), [STAT2 p.Pro489Leu](/variant/stat2-p-pro489leu), [STAT2 p.Pro489Ala](/variant/stat2-p-pro489ala), [STAT2 p.Pro489Thr](/variant/stat2-p-pro489thr), [STAT2 p.Arg667Ter](/variant/stat2-p-arg667ter), [STAT2 p.Gln274Ter](/variant/stat2-p-gln274ter), [STAT2 p.Ala219Thr](/variant/stat2-p-ala219thr), [STAT2 p.Ala302Thr](/variant/stat2-p-ala302thr).

### Data sources & attribution {#sources}

ClinVar (NCBI — public domain, built 2026-10-14); gnomAD v4.1 (Broad Institute, built 2026-10-14); 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 2026-10-14); 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 845773). 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.*