# NM_001458.5(FLNC):c.2154G>C (p.Val718=)

https://sugi.bio/variant/flnc-p-val718

## Summary

**FLNC p.Val718= (c.2154G>C)** is classified **Likely benign** in FLNC (ClinVar, Single submitter, 1 submitter; last evaluated 2024-10-22). Absent from gnomAD v4.1; Associated with Cardiovascular phenotype.

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

## For patients & families {#patients}

This is a change in the FLNC gene that is classified as likely benign — not considered disease-causing, submitted by 1 submitter, 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 | [FLNC](https://sugi.bio/atlas/gene/FLNC/) |
| Protein change (HGVS p.) | p.Val718= |
| Coding change (HGVS c.) | c.2154G>C |
| MANE Select transcript | [NM_001458](https://www.ncbi.nlm.nih.gov/nuccore/NM_001458) |
| Variant type | single nucleotide variant |
| Location | chr7:128842263-128842263 (GRCh38) |
| ClinVar | [VCV3515962](https://www.ncbi.nlm.nih.gov/clinvar/variation/3515962/) |

**All HGVS expressions:** `LRG_870:g.16835G>C`, `LRG_870t1:c.2154G>C`, `NC_000007.13:g.128482317G>C`, `NC_000007.14:g.128842263G>C`, `NG_011807.1:g.16835G>C`, `NG_178719.1:g.151G>C`, `NM_001127487.2:c.2154G>C`, `NM_001458.5:c.2154G>C`

## 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 2.283, phastCons 1 — highly conserved position (PP3-type support)
- CADD: **PHRED 8.346**. 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: **below the reporting threshold**. This position is scored for a different substitution (G>A, Δ0.45 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: **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}

**FLNC** population constraint: LOEUF 0.424, pLI 1, missense-Z 5.9661; 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):

- **myofibrillar myopathy** — Definitive (AD)
- **dilated cardiomyopathy** — Definitive (AD)

## Protein context {#protein}

Residue **718** lies in a β-strand.

**14 experimental structure(s)** (PDB): [1V05](https://www.rcsb.org/structure/1V05), [2D7M](https://www.rcsb.org/structure/2D7M), [2D7N](https://www.rcsb.org/structure/2D7N), [2D7O](https://www.rcsb.org/structure/2D7O), [2D7P](https://www.rcsb.org/structure/2D7P), [2D7Q](https://www.rcsb.org/structure/2D7Q).

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

*Describes the biological roles of FLNC (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:** FLNC's established molecular role includes cytoskeletal protein binding.


### Pathways affected {#pathways}

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

| Pathway (Reactome) | Evidence |
| --- | --- |
| [Cell-extracellular matrix interactions](https://reactome.org/content/detail/R-HSA-446353) | curated |

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

**Molecular function:** cytoskeletal protein binding, ankyrin binding, identical protein binding.

**Biological process:** sarcomere organization.

## Clinical significance {#significance}

**Likely benign** — review status Single submitter *(criteria provided, single submitter)*, last evaluated 2024-10-22.

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

### Submitter classifications {#submitters}

| Submitter | Classification | Review | Method | Date |
| --- | --- | --- | --- | --- |
| Ambry Genetics | Likely benign | criteria provided, single submitter | clinical testing | 2024-10-22 |

## Associated conditions {#conditions}

[Cardiovascular phenotype](https://sugi.bio/atlas/disease/cardiovascular-phenotype/).

**Reported phenotype names (ClinVar):** Cardiovascular phenotype.

## Similar variants {#similar}

Related FLNC variant pages (same residue, condition, or type): [FLNC c.1210+1G>A](/variant/flnc-c-1210-plus-1g-a), [FLNC c.2550+2T>C](/variant/flnc-c-2550-plus-2t-c), [FLNC c.2930-1G>A](/variant/flnc-c-2930-minus-1g-a), [FLNC c.5199+1G>T](/variant/flnc-c-5199-plus-1g-t), [FLNC c.5398+1G>C](/variant/flnc-c-5398-plus-1g-c), [FLNC p.Arg1313Ter](/variant/flnc-p-arg1313ter), [FLNC p.Arg1341Ter](/variant/flnc-p-arg1341ter), [FLNC p.Arg1657Ter](/variant/flnc-p-arg1657ter).

### 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 3515962). 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.*