Is FLNC p.Val1333= (c.3999C>T) pathogenic?

FLNC p.Val1333= (c.3999C>T) is classified Likely benign in FLNC (ClinVar, Single submitter, 1 submitter; last evaluated 2025-08-13). Very rare (popmax 0.0011%, sas); Associated with distal myopathy with posterior leg and anterior hand involvement.

What condition is associated with FLNC p.Val1333= (c.3999C>T)?

FLNC p.Val1333= (c.3999C>T) is associated with distal myopathy with posterior leg and anterior hand involvement, myofibrillar myopathy 5, hypertrophic cardiomyopathy 26 (ClinVar).

How common is FLNC p.Val1333= (c.3999C>T) in the general population?

FLNC p.Val1333= (c.3999C>T) is very rare (popmax 0.0011%, sas) (gnomAD).

FLNC p.Val1333=

Q: How is FLNC-related handgrip and calf weakness-distal myopathy inherited?

Typically Autosomal dominant (Orphanet). A genetic counselor can assess individual risk for a family.

c.3999C>T · rs1341936427 · VCV1156357

Likely benign Single submitter

Classification

Likely benign

ClinVar

Review

Single submitter ★☆☆☆

ClinVar · 1 submitter

gnomAD v4.1

Rare

very rare (popmax 0.0011%, sas)

Conditions

distal myopathy with posterior leg and anterior hand involvement

Computational evidence

Protein change
Missense predictors do not apply to this variant type; conservation carries the signal.
Splicing
SpliceAI	—	not assessed · no allele here is in the release
Constraint at this position
Conservation	phyloP -7.5
Overall
CADD	0.641	PHRED · no single calibrated threshold — expert panels disagree

Population frequency

gnomAD v4.1 · exomes + genomes

Grpmax group 0.0011% South Asian · 1/91,082 alleles

Filtering AF 0.000124% ClinGen BA1/BS1 input FAF95, joint · FAF99 9e-05%

Overall 0.000372% 6/1,613,790 alleles · very rare exomes 6/1,461,528 · genomes 0/152,262 · joint denominator

Ancestry group	Frequency	1 in
South Asiangrpmax	0.0011%	91,082
European (non-Finnish)	0.000424%	236,000

Rarity supports pathogenicity (ACMG PM2); frequency above a disease-specific BA1/BS1 threshold argues against it. A variant frequent in one ancestry group can be near-absent in others, so a single global figure can mislead.

Variant & gene context

Gene: FLNC
Protein: p.Val1333=
Coding: c.3999C>T
MANE Select: NM_001458
dbSNP: rs1341936427
Type: single nucleotide variant
Location: chr7:128846335 (GRCh38)
Gene constraint: LOEUF 0.424 · pLI 1.00 · ClinGen HI 3/3 (gnomAD)

Full FLNC gene report on Sugi Atlas → Gene function, pathways, protein structure, interactions & more

Disease context

distal myopathy with posterior leg and anterior hand involvement — disease report on Sugi Atlas → Associated genes, phenotypes, clinical trials & treatments

Also linked: myofibrillar myopathy 5 hypertrophic cardiomyopathy 26

For FLNC-related handgrip and calf weakness-distal myopathy (Orphanet):

Inheritance: Autosomal dominant
Onset: Adolescent, Adult

Similar variants

FLNC p.Val1333Ile Uncertain significance ★ same residue
FLNC c.1047+1G>T Likely pathogenic ★★ same condition
FLNC c.1048-1G>A Likely pathogenic ★★ same condition
FLNC c.1210+1G>A Likely pathogenic ★★ same condition
FLNC c.1549+2T>G Likely pathogenic ★★ same condition
FLNC c.2007+1G>A Likely pathogenic ★★ same condition
FLNC c.2550+1G>C Likely pathogenic ★★ same condition
FLNC c.2550+2T>C Pathogenic/Likely pathogenic ★★ same condition

Built on 18 open, versioned datasets — ClinVar, gnomAD, AlphaMissense, REVEL, ClinGen & more — plus Sugi Variant's own cross-source analysis. Source data 2026-01–2026-10, ClinVar 2026-10. Full sources & versions →

Cite Sugi Variant

Gür T. Sugi Variant: A Deterministic Per-Variant Germline Reference from a Knowledge Graph for Humans and AI Agents. 2026. doi:10.5281/zenodo.21509445. This variant: https://sugi.bio/variant/flnc-p-val1333 (accessed [today's date]).

Preprint & method: sugi.bio/variant/method Machine-readable: this page as Markdown