# NM_004006.3(DMD):c.1869C>G (p.Leu623=)

https://sugi.bio/variant/dmd-p-leu623

## Summary

**DMD p.Leu623= (c.1869C>G)** is classified **Benign/Likely benign** in DMD (ClinVar, Multiple submitters, 8 submitters; last evaluated 2026-02-03). Rare (popmax 0.169%, eas); Associated with Cardiovascular phenotype.

**At a glance:** Benign/Likely benign · review: Multiple submitters · rsID rs1800267 · 8 submitters · 4 linked conditions · rare (popmax 0.169%, eas)

## For patients & families {#patients}

This is a change in the DMD gene that is classified as benign/likely benign — not considered disease-causing, submitted by 8 submitters, and is linked to Cardiovascular phenotype.

*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 | [DMD](https://sugi.bio/atlas/gene/DMD/) |
| Protein change (HGVS p.) | p.Leu623= |
| Coding change (HGVS c.) | c.1869C>G |
| MANE Select transcript | [NM_004006](https://www.ncbi.nlm.nih.gov/nuccore/NM_004006) |
| dbSNP | [rs1800267](https://www.ncbi.nlm.nih.gov/snp/rs1800267/) |
| Variant type | single nucleotide variant |
| Location | chrX:32565825-32565825 (GRCh38) |
| ClinVar | [VCV388592](https://www.ncbi.nlm.nih.gov/clinvar/variation/388592/) |

**All HGVS expressions:** `LRG_199:g.778785C>G`, `LRG_199t1:c.1869C>G`, `NC_000023.10:g.32583942G>C`, `NC_000023.11:g.32565825G>C`, `NG_012232.1:g.778785C>G`, `NM_000109.4:c.1845C>G`, `NM_004006.3:c.1869C>G`, `NM_004009.3:c.1857C>G`, `NM_004010.3:c.1500C>G`

## 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 0.828, GERP -1.53, phastCons 0.999 — weakly conserved position
- CADD: **PHRED 3.262**. 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.*
- SpliceAI: **not assessed** — no allele at this position is in our SpliceAI release, either because it lies outside the scored MANE transcript scope or because every allele is below Δ0.2. We cannot tell which, so this claims neither; absence is not evidence against a splicing effect.
- Population frequency (gnomAD v4.1): grpmax **0.169%** (eas) · FAF95 0.134% · FAF99 0.121% · 57/33,733 in the highest group · 92/1,209,416 alleles overall — rare (popmax 0.169%, eas).

| Ancestry group | Allele frequency | 1 in |
| --- | --- | --- |
| East Asian (grpmax) | 0.169% | 592 |
| Remaining individuals (not grpmax-eligible) | 0.0735% | 1,360 |

*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}

**DMD** population constraint: ClinGen dosage — haploinsufficiency 3, 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):

- **progressive muscular dystrophy** — Definitive (XL)

## Protein context {#protein}

Residue **623** lies in a UniProt-annotated variant site (in).

**6 experimental structure(s)** (PDB): [1DXX](https://www.rcsb.org/structure/1DXX), [1EG3](https://www.rcsb.org/structure/1EG3), [1EG4](https://www.rcsb.org/structure/1EG4), [3UUN](https://www.rcsb.org/structure/3UUN), [9D58](https://www.rcsb.org/structure/9D58), [9EC1](https://www.rcsb.org/structure/9EC1).

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

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


### Pathways affected {#pathways}

DMD participates in **3 Reactome pathways** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| [Striated Muscle Contraction](https://reactome.org/content/detail/R-HSA-390522) | curated |
| [Formation of the dystrophin-glycoprotein complex (DGC)](https://reactome.org/content/detail/R-HSA-9913351) | electronic |
| [Non-integrin membrane-ECM interactions](https://reactome.org/content/detail/R-HSA-3000171) | electronic |

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

**Molecular function:** dystroglycan binding, actin binding, structural constituent of muscle, myosin binding, vinculin binding.

**Biological process:** regulation of heart rate, intracellular protein localization, positive regulation of neuron projection development, peptide biosynthetic process, positive regulation of neuron differentiation, cardiac muscle contraction.

## Clinical significance {#significance}

**Benign/Likely benign** — review status Multiple submitters *(criteria provided, multiple submitters, no conflicts)*, last evaluated 2026-02-03.

**Submitter consensus:** conflicting (6 Likely benign, 2 Benign).

**Submission history:** 8 submissions (2016–2026); classifications have differed over time.

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| Ambry Genetics | Likely benign | criteria provided, single submitter | clinical testing | 2019-01-28 |
| PreventionGenetics, part of Exact Sciences | Likely benign | no assertion criteria provided | clinical testing | 2019-09-03 |
| Blueprint Genetics | Likely benign | criteria provided, single submitter | clinical testing | 2024-11-20 |
| Natera, Inc. | Likely benign | no assertion criteria provided | clinical testing | 2019-06-24 |
| GeneDx | Benign | criteria provided, single submitter | clinical testing | 2021-01-14 |
| Eurofins Ntd Llc (ga) | Likely benign | criteria provided, single submitter | clinical testing | 2016-10-27 |
| Mayo Clinic Laboratories, Mayo Clinic | Likely benign | criteria provided, single submitter | clinical testing | 2025-07-15 |
| Labcorp Genetics (formerly Invitae), Labcorp | Benign | criteria provided, single submitter | clinical testing | 2026-02-03 |

## Associated conditions {#conditions}

[Cardiovascular phenotype](https://sugi.bio/atlas/disease/cardiovascular-phenotype/), [cardiomyopathy](https://sugi.bio/atlas/disease/cardiomyopathy/), [Becker muscular dystrophy](https://sugi.bio/atlas/disease/becker-muscular-dystrophy/), [Duchenne muscular dystrophy](https://sugi.bio/atlas/disease/duchenne-muscular-dystrophy/).

**Reported phenotype names (ClinVar):** Cardiovascular phenotype, not specified, Duchenne muscular dystrophy, not provided, Becker muscular dystrophy, Cardiomyopathy, Dystrophin deficiency, DMD-related disorder, MUSCULAR DYSTROPHY, PSEUDOHYPERTROPHIC PROGRESSIVE, DUCHENNE TYPE, Duchenne Muscular Dystrophy (DMD).

## Similar variants {#similar}

Related DMD variant pages (same residue, condition, or type): [DMD p.Leu623Phe](/variant/dmd-p-leu623phe), [DMD c.10086+1G>A](/variant/dmd-c-10086-plus-1g-a), [DMD c.10086+1G>T](/variant/dmd-c-10086-plus-1g-t), [DMD c.10086+2T>C](/variant/dmd-c-10086-plus-2t-c), [DMD c.10087-2A>G](/variant/dmd-c-10087-minus-2a-g), [DMD c.10223+1G>A](/variant/dmd-c-10223-plus-1g-a), [DMD c.10223+1G>C](/variant/dmd-c-10223-plus-1g-c), [DMD c.10224-2A>G](/variant/dmd-c-10224-minus-2a-g).

### 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 388592). 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.*