rs199473233

chr3-38560335-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_001099404.2(SCN5A):c.4057G>A(p.Val1353Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000149 in 1,614,100 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/23 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. V1353V) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000015 (0 hom.)
• Consequence: SCN5A NM_001099404.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:10 B:1 O:2
• Conservation: PhyloP100: 7.83

Genes affected

SCN5A (HGNC:10593): (sodium voltage-gated channel alpha subunit 5) The protein encoded by this gene is an integral membrane protein and tetrodotoxin-resistant voltage-gated sodium channel subunit. This protein is found primarily in cardiac muscle and is responsible for the initial upstroke of the action potential in an electrocardiogram. Defects in this gene have been associated with long QT syndrome type 3 (LQT3), atrial fibrillation, cardiomyopathy, and Brugada syndrome 1, all autosomal dominant cardiac diseases. Alternative splicing results in several transcript variants encoding different isoforms. [provided by RefSeq, May 2022]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a transmembrane_region Helical; Name=S5 of repeat III (size 19) in uniprot entity SCN5A_HUMAN there are 9 pathogenic changes around while only 0 benign (100%) in NM_001099404.2
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, SCN5A
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SCN5A	NM_001099404.2	c.4057G>A	p.Val1353Met	missense_variant	23/28	ENST00000413689.6
SCN5A	NM_000335.5	c.4054G>A	p.Val1352Met	missense_variant	23/28	ENST00000423572.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SCN5A	ENST00000413689.6	c.4057G>A	p.Val1353Met	missense_variant	23/28	5	NM_001099404.2	P4
SCN5A	ENST00000423572.7	c.4054G>A	p.Val1352Met	missense_variant	23/28	1	NM_000335.5	A1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152210 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000278 AC: 7 AN: 251488 Hom.: 0 AF XY: 0.0000294 AC XY: 4 AN XY: 135918

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000289

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000352

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000150 AC: 22 AN: 1461890 Hom.: 0 Cov.: 32 AF XY: 0.0000165 AC XY: 12 AN XY: 727246

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000153

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152210 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74354

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000278 Hom.: 0

Bravo AF: 0.0000151

ExAC AF: 0.0000494 AC: 6

EpiCase AF: 0.000109

EpiControl AF: 0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:10 Benign:1 Other:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 04, 2023	This variant is present in population databases (rs199473233, gnomAD 0.006%). 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. Experimental studies have shown that this missense change does not substantially affect SCN5A function (PMID: 32533946). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 67857). This variant is also known as p.V1352M. This missense change has been observed in individual(s) with clinical features of SCN5A-related conditions (PMID: 20129283, 28074886, 29540472, 30086531, 31737537, 32880476, 33221895, 33996946). This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 1353 of the SCN5A protein (p.Val1353Met). -
Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Mar 01, 2019	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Apr 06, 2021	Reported in association with Brugada syndrome, sudden infant death syndrome, and left ventricular dysfunction (Kapplinger et al., 2010; Neubauer et al., 2017; Hazebroek et al., 2018); Identified in patients referred for Brugada syndrome or Long QT syndrome genetic testing at GeneDx and found to segregate with disease in one relative; In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID#67857; Landrum et al., 2016); This variant is associated with the following publications: (PMID: 30086531, 24136861, 20129283, 28074886, 26746457, 28150151, 29540472, 30662450, 31737537, 32569262, 33221895, 32533946, 32880476) -

Cardiac arrhythmia Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Dec 18, 2023	This missense variant replaces valine with methionine at codon 1353 of the SCN5A protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). This variant is found within a highly conserved region of the transmembrane domain DIII. Rare nontruncating variants in this region (a.a. 1207-1466) have been shown to be significantly overrepresented in individuals with Brugada syndrome (PMID: 32893267). A functional study has shown that this variant does not change channel peak current density in transfected cells (PMID: 32533946). This variant has been reported in at least five individuals affected with Brugada syndrome (PMID: 24136861, 33221895, 32893267, 36516610, 36724992), in four individuals suspected of having Brugada syndrome (PMID: 20129283) or long QT syndrome (PMID: 31737537, ClinVar SCV000235469.11). This variant has also been reported in individuals affected with sudden infant death syndrome (PMID: 28074886, 30086531), left ventricular dysfunction (PMID: 29540472), and dilated cardiomyopathy (PMID: 32880476). This variant has been identified in 7/251488 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Although there is a suspicion for a pathogenic role, the available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Nov 20, 2023	This missense variant replaces valine with methionine at codon 1353 of the SCN5A protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). This variant is found within a highly conserved region of the transmembrane domain DIII. Rare nontruncating variants in this region (a.a. 1207-1466) have been shown to be significantly overrepresented in individuals with Brugada syndrome (PMID: 32893267). A functional study has shown that this variant does not change channel peak current density in transfected cells (PMID: 32533946). This variant has been reported in at least five individuals affected with Brugada syndrome (PMID: 24136861, 33221895, 32893267, 36516610, 36724992), in four individuals suspected of having Brugada syndrome (PMID: 20129283) or long QT syndrome (PMID: 31737537, ClinVar SCV000235469.11). This variant has also been reported in individuals affected with sudden infant death syndrome (PMID: 28074886, 30086531), left ventricular dysfunction (PMID: 29540472), and dilated cardiomyopathy (PMID: 32880476). This variant has been identified in 7/251488 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Although there is a suspicion for a pathogenic role, the available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Brugada syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 28, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Ventricular fibrillation, paroxysmal familial, type 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 28, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Dilated cardiomyopathy 1E Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 28, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Progressive familial heart block, type 1A Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 28, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Long QT syndrome 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 28, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Sick sinus syndrome 1 Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Apr 28, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Dilated cardiomyopathy 1E;C4551804:Brugada syndrome 1 Other:1

not provided, no classification provided

phenotyping only

GenomeConnect - Invitae Patient Insights Network

-

Variant interpreted as Uncertain significance and reported on 09-11-2019 by Invitae. GenomeConnect-Invitae Patient Insights Network assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. Registry team members make no attempt to reinterpret the clinical significance of the variant. Phenotypic details are available under supporting information. -

Brugada syndrome Other:1

not provided, no classification provided

literature only

Cardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust

-

This variant has been reported as associated with Brugada syndrome in the following publications (PMID:20129283). This is a literature report, and does not necessarily reflect the clinical interpretation of the Imperial College / Royal Brompton Cardiovascular Genetics laboratory. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.83
CardioboostArm	Pathogenic	1.0
CardioboostCm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.58
Cadd	Pathogenic	28
Dann	Pathogenic	1.0
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Uncertain	0.93	D
M_CAP	Pathogenic	0.83	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-2.9	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.94
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D;D
Polyphen		0.99	D;D;.;D;.;D;D;.;.
Vest4		0.98
MutPred		0.90		Loss of catalytic residue at V1353 (P = 0.0469);.;Loss of catalytic residue at V1353 (P = 0.0469);Loss of catalytic residue at V1353 (P = 0.0469);.;Loss of catalytic residue at V1353 (P = 0.0469);.;.;.;
MVP		0.99
MPC		1.4
ClinPred		0.94	D
GERP RS		4.3
Varity_R		0.70
gMVP		0.98

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: rs199473233; hg19: chr3-38601826; COSMIC: COSV61114948;