3-38566531-C-G

Variant names:

• chr3-38566531-C-G
• rs199473211
• NM_001099404.2:c.3718G>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_001099404.2(SCN5A):​c.3718G>C​(p.Glu1240Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000297 in 1,614,010 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 0.000020 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000031 (0 hom.)
• Consequence: SCN5A NM_001099404.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:5 B:1 O:1
• Conservation: PhyloP100: 7.91
• Publications: 13 publications found

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 Gene-Disease associations (from GenCC):

• Brugada syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Brugada syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1E

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• familial long QT syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• long QT syndrome 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• sick sinus syndrome 1

  Inheritance: AD, AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
• progressive familial heart block, type 1A

  Inheritance: SD, AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Genomics England PanelApp
• atrial standstill

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial atrial fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial sick sinus syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• paroxysmal familial ventricular fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• progressive familial heart block

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• catecholaminergic polymorphic ventricular tachycardia

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• short QT syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.925

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.3718G>C	p.Glu1240Gln	missense_variant	Exon 21 of 28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.3715G>C	p.Glu1239Gln	missense_variant	Exon 21 of 28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.3718G>C	p.Glu1240Gln	missense_variant	Exon 21 of 28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.3715G>C	p.Glu1239Gln	missense_variant	Exon 21 of 28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152224 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000294

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000398 AC: 10 AN: 251026 AF XY: 0.0000221

Gnomad AFR exome AF: 0.0000621

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000792

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000308 AC: 45 AN: 1461786 Hom.: 0 Cov.: 31 AF XY: 0.0000234 AC XY: 17 AN XY: 727200

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53356

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000378 AC: 42 AN: 1111980

Other (OTH) AF: 0.0000497 AC: 3 AN: 60394

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152224 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74358

African (AFR) AF: 0.0000241 AC: 1 AN: 41460

American (AMR) AF: 0.00 AC: 0 AN: 15282

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5202

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000294 AC: 2 AN: 68044

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.0000216 Hom.: 0

Bravo AF: 0.0000264

ESP6500AA AF: 0.00 AC: 0

ESP6500EA AF: 0.000116 AC: 1

ExAC AF: 0.0000412 AC: 5

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

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

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:2

Jan 08, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with glutamine, which is neutral and polar, at codon 1240 of the SCN5A protein (p.Glu1240Gln). This variant is present in population databases (rs199473211, gnomAD 0.007%). This missense change has been observed in individuals with Brugada syndrome and/or SCN5A-related conditions (PMID: 11901046, 30203441, 37937776). This variant is also known as c.3715G>C, p.Glu1239Gln. ClinVar contains an entry for this variant (Variation ID: 67818). 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. 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. -

Jul 10, 2019

Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiac arrhythmia Uncertain:2

Apr 15, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces glutamic acid with glutamine at codon 1240 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 does not affect the channel function (PMID: 30891416). This variant has been reported in an individual affected with Brugada syndrome (PMID: 11901046). This variant has aslo been reported in an individual affected with unexplained sudden cardiac arrest and recurrent ventricular tachycardia and ventricular fibrillation episodes (PMID: 30891416). However, no Brugada ECG pattern was observed in this individual or five other asymptomatic family member carriers. This variant has also been identified in 10/251026 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. -

Jul 20, 2024

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces glutamic acid with glutamine at codon 1240 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 does not affect the channel function (PMID: 30891416). This variant has been reported in an individual affected with Brugada syndrome (PMID: 11901046). This variant has aslo been reported in an individual affected with unexplained sudden cardiac arrest and recurrent ventricular tachycardia and ventricular fibrillation episodes (PMID: 30891416). However, no Brugada ECG pattern was observed in this individual or five other asymptomatic family member carriers. This variant has also been identified in 10/251026 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 Pathogenic:1

Apr 18, 2016

Clinical Molecular Genetics Laboratory, Johns Hopkins All Children's Hospital

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

SUDDEN INFANT DEATH SYNDROME;C1832680:Dilated cardiomyopathy 1E;C1837845:Sick sinus syndrome 1;C1859062:Long QT syndrome 3;C1879286:Progressive familial heart block, type 1A;C2751898:Ventricular fibrillation, paroxysmal familial, type 1;C3151464:Atrial fibrillation, familial, 10;C4551804:Brugada syndrome 1 Uncertain:1

Jul 22, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiovascular phenotype Benign:1

Feb 07, 2023

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Brugada syndrome Other:1

-

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

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

This variant has been reported as associated with Brugada syndrome in the following publications (PMID:11901046). 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	Benign	0.25
CardioboostArm	Pathogenic	1.0
CardioboostCm	Uncertain	0.43
BayesDel_addAF	Pathogenic	0.29	D
BayesDel_noAF	Pathogenic	0.36
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	.;.;.;.;.;D;.;.;.
Eigen	Pathogenic	0.78
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	.;D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.60	D
MetaRNN	Pathogenic	0.92	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.8	.;.;.;.;.;M;.;.;.
PhyloP100		7.9
PrimateAI	Uncertain	0.66	T
PROVEAN	Uncertain	-2.8	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0010	D;D;D;D;D;D;D;D;D
Sift4G	Benign	0.070	T;T;T;T;T;T;T;T;T
Polyphen		0.98	D;D;.;D;.;P;D;.;.
Vest4		0.85
MVP		0.98
MPC		1.4
ClinPred		0.74	D
GERP RS		4.5
Varity_R		0.72
gMVP		0.89
Mutation Taster		=0/100	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: rs199473211; hg19: chr3-38608022; COSMIC: COSV61124264;