rs755583250

Positions:

• chr7-128837503-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001458.5(FLNC):​c.805C>T​(p.Arg269*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,856 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: FLNC NM_001458.5 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 1.09

Genes affected

FLNC (HGNC:3756): (filamin C) This gene encodes one of three related filamin genes, specifically gamma filamin. These filamin proteins crosslink actin filaments into orthogonal networks in cortical cytoplasm and participate in the anchoring of membrane proteins for the actin cytoskeleton. Three functional domains exist in filamin: an N-terminal filamentous actin-binding domain, a C-terminal self-association domain, and a membrane glycoprotein-binding domain. Mutations in this gene are a cause of cardiopathy. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-128837503-C-T is Pathogenic according to our data. Variant chr7-128837503-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 539411.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr7-128837503-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FLNC	NM_001458.5	c.805C>T	p.Arg269*	stop_gained	4/48	ENST00000325888.13	NP_001449.3
FLNC	NM_001127487.2	c.805C>T	p.Arg269*	stop_gained	4/47		NP_001120959.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FLNC	ENST00000325888.13	c.805C>T	p.Arg269*	stop_gained	4/48	1	NM_001458.5	ENSP00000327145.8
FLNC	ENST00000346177.6	c.805C>T	p.Arg269*	stop_gained	4/47	1		ENSP00000344002.6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000401 AC: 1 AN: 249664 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135444

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000883

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461856 Hom.: 0 Cov.: 36 AF XY: 0.00 AC XY: 0 AN XY: 727224

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Aug 26, 2022

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at a significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 31514951, 30067491, 32112656) -

Cardiovascular phenotype Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 20, 2023

The p.R269* pathogenic mutation (also known as c.805C>T), located in coding exon 4 of the FLNC gene, results from a C to T substitution at nucleotide position 805. This changes the amino acid from an arginine to a stop codon within coding exon 4. This variant has been detected in an individual with dilated cardiomyopathy and recurrent sustained ventricular tachycardia (Begay RL et al. JACC Clin Electrophysiol, 2018 Apr;4:504-514). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. Based on the supporting evidence, this variant is expected to be causative of FLNC-related dilated cardiomyopathy; however, its clinical significance for FLNC-related hypertrophy/restrictive cardiomyopathy and/or skeletal myopathy is unclear. -

Myofibrillar myopathy 5;C3279722:Distal myopathy with posterior leg and anterior hand involvement;C4310749:Hypertrophic cardiomyopathy 26;CN239310:Dilated Cardiomyopathy, Dominant Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 09, 2023

This premature translational stop signal has been observed in individual(s) with dilated cardiomyopathy (PMID: 30067491). This variant is present in population databases (rs755583250, gnomAD 0.0009%). This sequence change creates a premature translational stop signal (p.Arg269*) in the FLNC gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in FLNC are known to be pathogenic (PMID: 27908349). ClinVar contains an entry for this variant (Variation ID: 539411). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.51
CADD	Pathogenic	39
DANN	Uncertain	1.0
Eigen	Uncertain	0.56
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Benign	0.42	N
Vest4		0.80
GERP RS		5.2

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs755583250; hg19: chr7-128477557; COSMIC: COSV57950044; COSMIC: COSV57950044;