# NM_001354604.2(MITF):c.1331_1343dup (p.Asp449fs)

https://sugi.bio/variant/mitf-p-asp449fs

## Summary

**MITF p.Asp449fs (c.1331_1343dup)** is classified **Pathogenic** in MITF (ClinVar, Single submitter, 1 submitter; last evaluated 2017-07-01). No gnomAD frequency available for this variant.

**At a glance:** Pathogenic · review: Single submitter · rsID rs2066649828 · 1 submitter · no gnomAD frequency available for this variant

## For patients & families {#patients}

This is a change in the MITF gene that is reported as disease-causing, but on limited review, 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 | [MITF](https://sugi.bio/atlas/gene/MITF/) |
| Protein change (HGVS p.) | p.Asp449fs |
| Coding change (HGVS c.) | c.1331_1343dup |
| MANE Select transcript | [NM_001354604](https://www.ncbi.nlm.nih.gov/nuccore/NM_001354604) |
| dbSNP | [rs2066649828](https://www.ncbi.nlm.nih.gov/snp/rs2066649828/) |
| Variant type | Duplication |
| Location | chr3:69964995-69964996 (GRCh38) |
| ClinVar | [VCV872078](https://www.ncbi.nlm.nih.gov/clinvar/variation/872078/) |

**All HGVS expressions:** `LRG_776:g.230517_230529dup`, `NC_000003.11:g.70014149_70014161dup`, `NC_000003.12:g.69964998_69965010dup`, `NG_011631.1:g.230517_230529dup`, `NM_000248.4:c.1010_1022dup`, `NM_001184967.2:c.1157_1169dup`, `NM_001354604.2:c.1331_1343dup`, `NM_001354605.2:c.1328_1340dup`, `NM_001354606.2:c.1310_1322dup`, `NM_001354607.2:c.1262_1274dup`, `NM_001354608.2:c.1157_1169dup`, `NM_006722.3:c.1310_1322dup`, `NM_198158.3:c.992_1004dup`, `NM_198159.3:c.1313_1325dup`, `NM_198177.3:c.1265_1277dup`, `NM_198178.3:c.824_836dup`

## Computational & population evidence {#evidence}

**Concordance:** 1 independent predictor **concordant** with the ClinVar classification.

- **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 4.316, GERP 1.3, phastCons 0.984 — highly conserved position (PP3-type support)
- Molecular consequence: **frameshift** — a predicted loss-of-function variant. ClinGen curates **sufficient evidence for haploinsufficiency** in this gene (constraint LOEUF 0.482, pLI 0.99203), supporting a loss-of-function disease mechanism. *Descriptive; not an applied PVS1 code.*
- Nonsense-mediated decay: the premature termination codon is **in the last exon (10 of 10)** — predicted to **escape NMD**, so the truncated protein is likely expressed. An input to PVS1, not an applied code.
- SpliceAI: **not assessed** — the release is built from a substitutions-only source, so it holds no duplication variants. That is a property of the dataset, not of the variant, and is not evidence against a splicing effect.
- Population frequency: **no gnomAD frequency available for this variant** — rarity (ACMG PM2) and BA1/BS1 cannot be assessed for this variant.

*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}

**MITF** population constraint: LOEUF 0.482, pLI 0.99203, missense-Z 1.0386; 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):

- **Waardenburg syndrome type 2** — Definitive (AD)

## Protein context {#protein}


AlphaFold model confidence (whole protein): pLDDT 62.25, 21% of residues very-high.

**12 experimental structure(s)** (PDB): [4C7N](https://www.rcsb.org/structure/4C7N), [7D8R](https://www.rcsb.org/structure/7D8R), [7D8S](https://www.rcsb.org/structure/7D8S), [7D8T](https://www.rcsb.org/structure/7D8T), [7EOD](https://www.rcsb.org/structure/7EOD), [8E1D](https://www.rcsb.org/structure/8E1D).

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

*Describes the biological roles of MITF (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:** MITF's established molecular role includes RNA polymerase II cis-regulatory region sequence-specific DNA binding.


### Pathways affected {#pathways}

MITF participates in **10 Reactome pathways** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| [SUMOylation of transcription factors](https://reactome.org/content/detail/R-HSA-3232118) | curated |
| [Regulation of MITF-M dependent genes involved in invasion](https://reactome.org/content/detail/R-HSA-9854909) | other |
| [Regulation of MITF-M dependent genes involved in metabolism](https://reactome.org/content/detail/R-HSA-9854907) | other |
| [Regulation of MITF-M-dependent genes involved in DNA replication, damage repair and senescence](https://reactome.org/content/detail/R-HSA-9825895) | other |
| [Regulation of MITF-M-dependent genes involved in apoptosis](https://reactome.org/content/detail/R-HSA-9824594) | other |
| [Regulation of MITF-M-dependent genes involved in cell cycle and proliferation](https://reactome.org/content/detail/R-HSA-9825892) | other |
| [Regulation of MITF-M-dependent genes involved in extracellular matrix, focal adhesion and epithelial-to-mesenchymal transition](https://reactome.org/content/detail/R-HSA-9926550) | other |
| [Regulation of MITF-M-dependent genes involved in lysosome biogenesis and autophagy](https://reactome.org/content/detail/R-HSA-9857377) | other |
| [Regulation of MITF-M-dependent genes involved in pigmentation](https://reactome.org/content/detail/R-HSA-9824585) | other |
| [Transcriptional and post-translational regulation of MITF-M expression and activity](https://reactome.org/content/detail/R-HSA-9856649) | electronic |

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

**Molecular function:** RNA polymerase II cis-regulatory region sequence-specific DNA binding, DNA-binding transcription activator activity, RNA polymerase II-specific, E-box binding.

**Biological process:** negative regulation of transcription by RNA polymerase II, regulation of DNA-templated transcription, positive regulation of gene expression, negative regulation of cell migration, positive regulation of DNA-templated transcription, positive regulation of transcription by RNA polymerase II.

## Clinical significance {#significance}

**Pathogenic** — review status Single submitter *(criteria provided, single submitter)*, last evaluated 2017-07-01.

**Submitter consensus:** unanimous (1/1 Pathogenic).

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| CeGaT Center for Human Genetics Tuebingen | Pathogenic | criteria provided, single submitter | clinical testing | 2017-07-01 |

**Reported phenotype names (ClinVar):** not provided, none provided.

## Similar variants {#similar}

Related MITF variant pages (same residue, condition, or type): [MITF p.Asp449Asn](/variant/mitf-p-asp449asn), [MITF c.1180-5_1203dup](/variant/mitf-c-1180-minus-5-1203dup), [MITF p.Arg217fs](/variant/mitf-p-arg217fs), [MITF p.Arg400Ter](/variant/mitf-p-arg400ter), [MITF p.Asn430fs](/variant/mitf-p-asn430fs), [MITF p.Cys431fs](/variant/mitf-p-cys431fs), [MITF p.Gln132fs](/variant/mitf-p-gln132fs), [MITF p.Gln365fs](/variant/mitf-p-gln365fs).

### 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 872078). 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.*