chr7-128848616-G-T

Variant names:

• chr7-128848616-G-T
• rs774263134
• NM_001458.5:c.4636G>T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_001458.5(FLNC):​c.4636G>T​(p.Gly1546Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1546S) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 33)
• Consequence: FLNC NM_001458.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.15
• Publications: 0 publications found

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]

FLNC Gene-Disease associations (from GenCC):

• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen, Ambry Genetics, G2P
• myofibrillar myopathy 5

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, ClinGen, G2P
• hypertrophic cardiomyopathy 26

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, PanelApp Australia
• distal myopathy with posterior leg and anterior hand involvement

  Inheritance: AD Classification: MODERATE, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics
• familial isolated restrictive cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• heart conduction disease

  Inheritance: AD Classification: LIMITED Submitted by: Genomics England PanelApp

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 16 uncertain in NM_001458.5
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-128848616-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 472074.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.97

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FLNC	NM_001458.5	c.4636G>T	p.Gly1546Cys	missense_variant	Exon 27 of 48	ENST00000325888.13	NP_001449.3
FLNC	NM_001127487.2	c.4636G>T	p.Gly1546Cys	missense_variant	Exon 27 of 47		NP_001120959.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FLNC	ENST00000325888.13	c.4636G>T	p.Gly1546Cys	missense_variant	Exon 27 of 48	1	NM_001458.5	ENSP00000327145.8

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Jul 28, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with FLNC-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces glycine with cysteine at codon 1546 of the FLNC protein (p.Gly1546Cys). The glycine residue is highly conserved and there is a large physicochemical difference between glycine and cysteine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.91	D;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	1.0	D;D
M_CAP	Pathogenic	0.69	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.2	H;H
PhyloP100		8.1
PrimateAI	Pathogenic	0.86	D
PROVEAN	Pathogenic	-7.7	D;D
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0020	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.86
MutPred		0.81		Loss of disorder (P = 0.0149);Loss of disorder (P = 0.0149);
MVP		0.92
MPC		1.0
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.97
gMVP		0.81
Mutation Taster		=17/83	disease causing

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

Other links and lift over

dbSNP: rs774263134; hg19: chr7-128488670;