# NM_000260.4(MYO7A):c.721C>T (p.Arg241Cys)

https://sugi.bio/variant/myo7a-p-arg241cys

## Summary

**MYO7A p.Arg241Cys (c.721C>T)** is classified **Pathogenic** in MYO7A (ClinVar, Multiple submitters, 10 submitters; last evaluated 2025-11-18). AlphaMissense: likely pathogenic (0.9889); Very rare (popmax 0.00133%, afr); Associated with Usher syndrome.

**At a glance:** Pathogenic · review: Multiple submitters · rsID rs782166819 · 10 submitters · 5 linked conditions · AlphaMissense likely pathogenic · very rare (popmax 0.00133%, afr)

## For patients & families {#patients}

This is a change in the MYO7A gene that is considered disease-causing, submitted by 10 submitters, and is linked to Usher syndrome.

*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) | Childhood, Infancy, Neonatal |
| Prevalence | 1-9 / 100 000 (Worldwide) |
| Clinical trials | 19 registered for this condition — see ClinicalTrials.gov |
| Diagnostic panels | MYO7A is a diagnostic-grade gene on 4 Genomics England panels |

**Commonly reported features of Usher syndrome** (across patients with this condition; presentation varies — frequencies from Orphanet):

- Sensorineural hearing impairment — Very frequent (99-80%)
- Visual impairment — Very frequent (99-80%)
- Abnormal electroretinogram — Very frequent (99-80%)
- Progressive visual loss — Very frequent (99-80%)
- Blindness — Very frequent (99-80%)
- Nyctalopia — Very frequent (99-80%)
- Visual field defect — Very frequent (99-80%)
- Abnormal vestibular function — Very frequent (99-80%)

**Support & next steps:** [Condition overview & support (NIH GARD)](https://rarediseases.info.nih.gov/diseases/0007843/index) · [Find a genetic counselor (NSGC)](https://findageneticcounselor.nsgc.org/).

## Identity {#identity}

| Field | Value |
| --- | --- |
| Gene | [MYO7A](https://sugi.bio/atlas/gene/MYO7A/) |
| Protein change (HGVS p.) | p.Arg241Cys |
| Coding change (HGVS c.) | c.721C>T |
| MANE Select transcript | [NM_000260](https://www.ncbi.nlm.nih.gov/nuccore/NM_000260) |
| dbSNP | [rs782166819](https://www.ncbi.nlm.nih.gov/snp/rs782166819/) |
| Variant type | single nucleotide variant |
| Location | chr11:77156990-77156990 (GRCh38) |
| ClinVar | [VCV438180](https://www.ncbi.nlm.nih.gov/clinvar/variation/438180/) |

**All HGVS expressions:** `LRG_1420:g.33745C>T`, `LRG_1420t1:c.721C>T`, `NC_000011.10:g.77156990C>T`, `NC_000011.9:g.76868036C>T`, `NG_009086.2:g.33745C>T`, `NM_000260.4:c.721C>T`, `NM_001127180.2:c.721C>T`, `NM_001369365.1:c.688C>T`

## Computational & population evidence {#evidence}

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

- AlphaMissense **likely pathogenic** (0.9889) — concordant with the pathogenic call
- REVEL 0.895 (moderately pathogenic-leaning) — agrees with AlphaMissense
- SaProt LLR -17.001 (damaging) — agrees with AlphaMissense
- → **In-silico consensus:** AlphaMissense, REVEL and SaProt all call this damaging
- Conservation: phyloP 4.738, GERP 1.91, phastCons 1 — highly conserved (agrees)
- CADD: **PHRED 27.1**. 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 0.95** across the covering region of the MANE Select transcript (77,130,635–77,214,693), spanning 84,058 bp. Chi-square p 0.0065. 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 (C>G, Δ0.77 donor 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 (gnomAD v4.1): grpmax **0.00133%** (afr) · FAF95 0.000689% · FAF99 0.000539% · 1/75,062 in the highest group · 16/1,613,268 alleles overall — very rare (popmax 0.00133%, afr).

| Ancestry group | Allele frequency | 1 in |
| --- | --- | --- |
| African / African-American (grpmax) | 0.00133% | 75,062 |
| European (non-Finnish) | 0.00119% | 84,259 |
| South Asian | 0.0011% | 91,064 |

*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}

**MYO7A** population constraint: LOEUF 0.995, pLI 2.4072e-62, missense-Z 0.076546. *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):

- **Usher syndrome type 1** — Definitive (AR)
- **nonsyndromic genetic hearing loss** — Definitive (AD)

## Protein context {#protein}

Residue **241** lies in the myosin motor domain; a UniProt-annotated variant site (in ush1b).

AlphaFold model confidence (whole protein): pLDDT 77.73, 16% of residues very-high.

**1 experimental structure(s)** (PDB): [5MV9](https://www.rcsb.org/structure/5MV9).

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

*Describes the biological roles of MYO7A (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:** MYO7A's established molecular role includes microfilament motor activity. p.Arg241Cys falls in the myosin motor domain.


### Pathways affected {#pathways}

MYO7A participates in **3 Reactome pathways** (⚕ = disease pathway):

| Pathway (Reactome) | Evidence |
| --- | --- |
| [The canonical retinoid cycle in rods (twilight vision)](https://reactome.org/content/detail/R-HSA-2453902) | curated |
| [Sensory processing of sound by inner hair cells of the cochlea](https://reactome.org/content/detail/R-HSA-9662360) | electronic |
| [Sensory processing of sound by outer hair cells of the cochlea](https://reactome.org/content/detail/R-HSA-9662361) | electronic |

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

**Molecular function:** microfilament motor activity, calmodulin binding, spectrin binding, actin filament binding.

**Biological process:** lysosome organization, visual perception, sensory perception of sound, actin filament-based movement, sensory perception of light stimulus, equilibrioception.

## Clinical significance {#significance}

**Pathogenic** — review status Multiple submitters *(criteria provided, multiple submitters, no conflicts)*, last evaluated 2025-11-18.

**Submitter consensus:** conflicting (7 Pathogenic, 3 Likely pathogenic).

**Submission history:** 10 submissions (2015–2025); classifications have differed over time.

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| Genomics England Pilot Project, Genomics England | Likely pathogenic | no assertion criteria provided | clinical testing |  |
| Women's Health and Genetics/Laboratory Corporation of America, LabCorp | Pathogenic | criteria provided, single submitter | clinical testing | 2024-01-26 |
| Counsyl | Likely pathogenic | no assertion criteria provided | clinical testing | 2017-04-12 |
| Revvity Omics, Revvity | Pathogenic | criteria provided, single submitter | clinical testing | 2025-02-07 |
| Labcorp Genetics (formerly Invitae), Labcorp | Pathogenic | criteria provided, single submitter | clinical testing | 2025-11-18 |
| Blueprint Genetics | Pathogenic | criteria provided, single submitter | clinical testing | 2019-10-07 |
| GeneDx | Pathogenic | criteria provided, single submitter | clinical testing | 2021-03-24 |
| Fulgent Genetics, Fulgent Genetics | Pathogenic | criteria provided, single submitter | clinical testing | 2024-01-27 |
| NIHR Bioresource Rare Diseases, University of Cambridge | Likely pathogenic | no assertion criteria provided | research | 2015-01-01 |
| Natera, Inc. | Pathogenic | criteria provided, single submitter | clinical testing | 2025-09-11 |

## Associated conditions {#conditions}

[Usher syndrome](https://sugi.bio/atlas/disease/usher-syndrome/), [Usher syndrome type 1](https://sugi.bio/atlas/disease/usher-syndrome-type-1/), [autosomal recessive nonsyndromic hearing loss 2](https://sugi.bio/atlas/disease/autosomal-recessive-nonsyndromic-hearing-loss-2/), [autosomal dominant nonsyndromic hearing loss 11](https://sugi.bio/atlas/disease/autosomal-dominant-nonsyndromic-hearing-loss-11/), [Usher syndrome type 1B](https://sugi.bio/atlas/disease/usher-syndrome-type-1b/).

**Reported phenotype names (ClinVar):** Usher syndrome, Autosomal recessive nonsyndromic hearing loss 2, Usher syndrome type 1, not provided, Usher syndrome type 1B, Autosomal dominant nonsyndromic hearing loss 11, MYO7A-related disorder, Usher Syndromes, Usher's syndrome, RETINITIS PIGMENTOSA AND CONGENITAL DEAFNESS.

## Same-residue context {#hotspot}

Residue **241** carries **3 other pathogenic ClinVar variants** — a recurrently-mutated position: [MYO7A p.Arg241Gly](/variant/myo7a-p-arg241gly), [MYO7A p.Arg241His](/variant/myo7a-p-arg241his), [MYO7A p.Arg241Leu](/variant/myo7a-p-arg241leu). *Positional co-occurrence of independent ClinVar records, not functional proof.*

## Similar variants {#similar}

Related MYO7A variant pages (same residue, condition, or type): [MYO7A p.Arg241Gly](/variant/myo7a-p-arg241gly), [MYO7A p.Arg241His](/variant/myo7a-p-arg241his), [MYO7A p.Arg241Leu](/variant/myo7a-p-arg241leu), [MYO7A p.Ala1288Pro](/variant/myo7a-p-ala1288pro), [MYO7A p.Arg1168Gln](/variant/myo7a-p-arg1168gln), [MYO7A p.Arg1873Gln](/variant/myo7a-p-arg1873gln), [MYO7A p.Arg395Cys](/variant/myo7a-p-arg395cys), [MYO7A p.Arg668Cys](/variant/myo7a-p-arg668cys).

### 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 438180). 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.*