# NM_001271.4(CHD2):c.3893= (p.Pro1298=)

https://sugi.bio/variant/chd2-p-pro1298

## Summary

**CHD2 p.Pro1298= (c.3893=)** is classified **Likely benign** in CHD2 (ClinVar, Single submitter, 1 submitter; last evaluated 2023-06-19). Absent from gnomAD v4.1.

**At a glance:** Likely benign · review: Single submitter · 1 submitter · absent from gnomAD v4.1

## For patients & families {#patients}

This is a change in the CHD2 gene that is classified as likely benign — not considered disease-causing, submitted by 1 submitter.

*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.*

**Support & next steps:** [Find a genetic counselor (NSGC)](https://findageneticcounselor.nsgc.org/).

## Identity {#identity}

| Field | Value |
| --- | --- |
| Gene | [CHD2](https://sugi.bio/atlas/gene/CHD2/) |
| Protein change (HGVS p.) | p.Pro1298= |
| Coding change (HGVS c.) | c.3893= |
| MANE Select transcript | [NM_001271](https://www.ncbi.nlm.nih.gov/nuccore/NM_001271) |
| Variant type | Variation |
| Location | chr15:92998506-92998506 (GRCh38) |
| ClinVar | [VCV4926718](https://www.ncbi.nlm.nih.gov/clinvar/variation/4926718/) |

**All HGVS expressions:** `LRG_1425:g.103186=`, `LRG_1425t1:c.3893=`, `NC_000015.10:g.92998506=`, `NC_000015.9:g.93541736=`, `NG_012826.2:g.103186=`, `NM_001271.4:c.3893=`

## Computational & population evidence {#evidence}

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

- **Missense predictors (AlphaMissense/REVEL/SaProt) do not apply** to this variant type — they score amino-acid substitutions only. For non-missense variants the computational signal comes from conservation (below), not from a missing predictor score.
- Conservation: phyloP 7.687, GERP 1.87, phastCons 1 — highly conserved position (PP3-type support)
- SpliceAI: **below the reporting threshold**. This position is scored for a different substitution (C>A, Δ0.39 acceptor gain), 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: **absent from gnomAD v4.1** — a rarity signal (ACMG PM2-supporting), not evidence of pathogenicity on its own.

*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}

**CHD2** population constraint: LOEUF 0.174, pLI 1, missense-Z 6.0349; ClinGen dosage — haploinsufficiency 3/3, triplosensitivity 0/3. *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):

- **complex neurodevelopmental disorder** — Definitive (AD)

## Protein context {#protein}

Residue **1298** lies in a UniProt-annotated variant site (in dee94); a UniProt-annotated variant site (found in a patient with progressive myoclonus epilepsy; uncertain significance).

AlphaFold model confidence (whole protein): pLDDT 60.81, 7% of residues very-high.

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

*Describes the biological roles of CHD2 (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:** CHD2's established molecular role includes RNA binding.


### Pathways affected {#pathways}

CHD2 participates in **1 Reactome pathway** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| [CHD1 and CHD2 subfamily](https://reactome.org/content/detail/R-HSA-9943411) | electronic |

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

**Molecular function:** RNA binding.

## Clinical significance {#significance}

**Likely benign** — review status Single submitter *(criteria provided, single submitter)*, last evaluated 2023-06-19.

**Submitter consensus:** unanimous (1/1 Likely benign).

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| Blueprint Genetics | Likely benign | criteria provided, single submitter | clinical testing | 2023-06-19 |

**Reported phenotype names (ClinVar):** not specified, AllHighlyPenetrant.

## Similar variants {#similar}

Related CHD2 variant pages (same residue, condition, or type): [CHD2 p.Pro1298Gln](/variant/chd2-p-pro1298gln), [CHD2 p.Pro1298Leu](/variant/chd2-p-pro1298leu), [CHD2 p.Lys173=](/variant/chd2-p-lys173).

### Data sources & attribution {#sources}

ClinVar (NCBI — public domain, built 2026-10-14); 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 2026-10-14); 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 4926718). 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.*