7-128830762-T-G

Variant names:

• chr7-128830762-T-G
• rs777706683
• NM_001458.5:c.125T>G

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 8P and 4B. PM1 PM2 PP3_Strong BS2

The NM_001458.5(FLNC):​c.125T>G​(p.Phe42Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000342 in 1,460,890 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 Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: FLNC NM_001458.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 6.16

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 Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a domain Calponin-homology (CH) 1 (size 106) in uniprot entity FLNC_HUMAN there are 4 pathogenic changes around while only 0 benign (100%) in NM_001458.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.963
• BS2: High AC in GnomAdExome4 at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FLNC	NM_001458.5	c.125T>G	p.Phe42Cys	missense_variant	Exon 1 of 48	ENST00000325888.13	NP_001449.3
FLNC	NM_001127487.2	c.125T>G	p.Phe42Cys	missense_variant	Exon 1 of 47		NP_001120959.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FLNC	ENST00000325888.13	c.125T>G	p.Phe42Cys	missense_variant	Exon 1 of 48	1	NM_001458.5	ENSP00000327145.8
FLNC	ENST00000346177.6	c.125T>G	p.Phe42Cys	missense_variant	Exon 1 of 47	1		ENSP00000344002.6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1460890 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726750

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: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

May 13, 2022

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Cardiovascular phenotype Uncertain:1

Jul 11, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.F42C variant (also known as c.125T>G), located in coding exon 1 of the FLNC gene, results from a T to G substitution at nucleotide position 125. The phenylalanine at codon 42 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

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

Dec 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces phenylalanine, which is neutral and non-polar, with cysteine, which is neutral and slightly polar, at codon 42 of the FLNC protein (p.Phe42Cys). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with FLNC-related conditions. ClinVar contains an entry for this variant (Variation ID: 642140). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on FLNC protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.38	D
BayesDel_noAF	Pathogenic	0.31
CADD	Pathogenic	31
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.97	D;.
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.74
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.33	D
MetaRNN	Pathogenic	0.96	D;D
MetaSVM	Uncertain	0.40	D
MutationAssessor	Pathogenic	4.0	H;H
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-6.2	D;D
REVEL	Pathogenic	0.89
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.94
MutPred		0.85		Gain of disorder (P = 0.0666);Gain of disorder (P = 0.0666);
MVP		0.85
MPC		2.6
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.88
gMVP		0.91

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs777706683; hg19: chr7-128470816;