3-38560374-C-T

Position:

chr3-38560374-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP2PP3_Strong

The NM_001099404.2(SCN5A):c.4018G>A(p.Val1340Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000235 in 1,614,198 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 Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

SCN5A
NM_001099404.2 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:5O:1

Conservation

PhyloP100: 6.09

Variant links:

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]

SCN5A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PM1

In a helix (size 24) in uniprot entity SCN5A_HUMAN there are 10 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 in gene, where missense usually causes diseases (based on misZ statistic), SCN5A. . Gene score misZ 2.7504 (greater than the threshold 3.09). Trascript score misZ 4.7729 (greater than threshold 3.09). GenCC has associacion of gene with progressive familial heart block, type 1A, Brugada syndrome, familial sick sinus syndrome, short QT syndrome, paroxysmal familial ventricular fibrillation, progressive familial heart block, long QT syndrome 3, familial atrial fibrillation, catecholaminergic polymorphic ventricular tachycardia, dilated cardiomyopathy, dilated cardiomyopathy 1E, arrhythmogenic right ventricular cardiomyopathy, Brugada syndrome 1, atrial standstill, familial isolated dilated cardiomyopathy, familial long QT syndrome, sick sinus syndrome 1.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.968

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN5A	NM_001099404.2 linkuse as main transcript	c.4018G>A	p.Val1340Ile	missense_variant	23/28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5 linkuse as main transcript	c.4015G>A	p.Val1339Ile	missense_variant	23/28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6 linkuse as main transcript	c.4018G>A	p.Val1340Ile	missense_variant	23/28	5	NM_001099404.2	ENSP00000410257	P4
SCN5A	ENST00000423572.7 linkuse as main transcript	c.4015G>A	p.Val1339Ile	missense_variant	23/28	1	NM_000335.5	ENSP00000398266	A1	Q14524-2

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152206

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000482

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000193

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000477

AC:

AN:

251416

Hom.:

AF XY:

0.0000368

AC XY:

AN XY:

135870

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000326

Gnomad SAS exome

AF:

0.0000653

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000233

AC:

AN:

1461874

Hom.:

Cov.:

AF XY:

0.0000193

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.0000597

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000756

Gnomad4 SAS exome

AF:

0.0000348

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000189

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152324

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74486

show subpopulations

Gnomad4 AFR

AF:

0.0000481

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000687

Hom.:

Bravo

AF:

0.0000416

ExAC

AF:

0.0000494

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:5Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Pathogenic:1Uncertain:1

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 19, 2024	This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 1340 of the SCN5A protein (p.Val1340Ile). This variant is present in population databases (rs199473605, gnomAD 0.04%). This missense change has been observed in individuals with Brugada syndrome (PMID: 19648062, 20129283, 20609320, 30662450; Invitae). ClinVar contains an entry for this variant (Variation ID: 67849). 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. Experimental studies have shown that this missense change affects SCN5A function (PMID: 19648062). For these reasons, this variant has been classified as Pathogenic. -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Dec 18, 2020	Reported in association with Brugada syndrome; however, this variant was also reported in multiple unaffected family members (Samani et al., 2009; Kapplinger et al., 2010; Garcia-Castro et al., 2010); In silico analysis supports that this missense variant does not alter protein structure/function; Functional studies suggest the presence of this variant may alter protein interactions under various experimental conditions; nevertheless, it is unclear how these studies may translate to a pathogenic role in vivo (Samani et al., 2009); Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID#67849; Landrum et al., 2016); This variant is associated with the following publications: (PMID: 25925977, 32268277, 19648062, 24136861, 20129283, 26633542, 25608792, 25904541, 25163546, 20609320, 22643347, 29557500, 30662450, 22581653, 33131149) -

Cardiac arrhythmia

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Oct 11, 2022	This missense variant replaces valine with isoleucine at codon 1340 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). A functional study has shown that this variant markedly reduces sodium currents in vitro (PMID: 19648062). This variant has been reported in four individuals affected with and in one individual suspected of having Brugada syndrome (PMID: 19648062, 20129283, 20609320, 30662450, 32268277), in four unaffected relatives from one of the affected families (PMID: 20609320), and in two individuals with borderline ECG alternations (PMID: 34428338). This variant has also been identified in 13/282822 chromosomes in the general population by the Genome Aggregation Database (gnomAD). 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	All of Us Research Program, National Institutes of Health	Apr 03, 2023	This missense variant replaces valine with isoleucine at codon 1340 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). A functional study has shown that this variant markedly reduces sodium currents in vitro (PMID: 19648062). This variant has been reported in four individuals affected with and in one individual suspected of having Brugada syndrome (PMID: 19648062, 20129283, 20609320, 30662450, 32268277), in four unaffected relatives from one of the affected families (PMID: 20609320), and in two individuals with borderline ECG alternations (PMID: 34428338). This variant has also been identified in 13/282822 chromosomes in the general population by the Genome Aggregation Database (gnomAD). 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. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Jul 17, 2024

Variant summary: SCN5A c.4018G>A (p.Val1340Ile) results in a conservative amino acid change located in the Ion transport domain (IPR005821) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4.8e-05 in 251416 control chromosomes. The observed variant frequency is approximately 2 fold of the estimated maximal expected allele frequency for a pathogenic variant in SCN5A causing Long QT Syndrome phenotype (2.1e-05). c.4018G>A has been reported in the literature in individuals affected with Brugada syndrome, complicated conditions of hyperthyroidism, and unspecified individuals from cohorts of Brugada syndrome/general control populations (example, Kapplinger_2010, Walsh_2014, Xu_2023, Yang_2022, Jain_2018, Denham_2019). These report(s) do not provide unequivocal conclusions about association of the variant with Long QT Syndrome. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in diminished sodium currents compared to the WT SCN5A in HEK-293 cells (Samani_2009). The following publications have been ascertained in the context of this evaluation (PMID: 30662450, 34621001, 30203441, 29557500, 20129283, 33131149, 19648062, 24136861, 37508981, 36129056). ClinVar contains an entry for this variant (Variation ID: 67849). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 30, 2022

The c.4018G>A (p.V1340I) alteration is located in exon 23 (coding exon 22) of the SCN5A gene. This alteration results from a G to A substitution at nucleotide position 4018, causing the valine (V) at amino acid position 1340 to be replaced by an isoleucine (I). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

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:19648062;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

0.58

CardioboostCm

Pathogenic

0.98

BayesDel_addAF

Pathogenic

0.33

BayesDel_noAF

Pathogenic

0.54

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Uncertain

0.76

.;.;.;.;.;D;.;.;.

Eigen

Pathogenic

0.75

Eigen_PC

Pathogenic

0.68

FATHMM_MKL

Uncertain

0.90

LIST_S2

Uncertain

0.96

.;D;D;D;D;D;D;.;D

M_CAP

Pathogenic

0.75

MetaRNN

Pathogenic

0.97

D;D;D;D;D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Pathogenic

3.0

.;.;.;.;.;M;.;.;.

MutationTaster

Benign

1.0

D;D;D;D;D;D;D;D;D;D

PrimateAI

Uncertain

0.76

PROVEAN

Benign

-0.97

N;N;N;N;N;N;N;N;N

REVEL

Pathogenic

0.86

Sift

Pathogenic

0.0

D;D;D;D;D;D;D;D;D

Sift4G

Uncertain

0.032

D;D;D;D;D;D;D;D;D

Polyphen

1.0

D;D;.;D;.;D;D;.;.

Vest4

0.96

MutPred

0.90

Loss of catalytic residue at V1340 (P = 0.1576);.;Loss of catalytic residue at V1340 (P = 0.1576);Loss of catalytic residue at V1340 (P = 0.1576);.;Loss of catalytic residue at V1340 (P = 0.1576);.;.;.;

MVP

0.98

MPC

1.3

ClinPred

0.53

GERP RS

4.3

Varity_R

0.63

gMVP

0.96

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.21

Details are displayed if max score is > 0.2

DS_AG_spliceai

0.21

Position offset: -29

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over