3-38560221-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1PM2PP2PP3_Moderate

The NM_001099404.2(SCN5A):c.4171G>A(p.Gly1391Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000279 in 1,613,876 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1391A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

SCN5A
NM_001099404.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:9

Conservation

PhyloP100: 1.81

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 7 ACMG points.

PM1

In a topological_domain Extracellular (size 51) in uniprot entity SCN5A_HUMAN there are 11 pathogenic changes around while only 1 benign (92%) 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, 0.845

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SCN5A	NM_001099404.2 linkuse as main transcript	c.4171G>A	p.Gly1391Arg	missense_variant	23/28	ENST00000413689.6
SCN5A	NM_000335.5 linkuse as main transcript	c.4168G>A	p.Gly1390Arg	missense_variant	23/28	ENST00000423572.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SCN5A	ENST00000413689.6 linkuse as main transcript	c.4171G>A	p.Gly1391Arg	missense_variant	23/28	5	NM_001099404.2	P4
SCN5A	ENST00000423572.7 linkuse as main transcript	c.4168G>A	p.Gly1390Arg	missense_variant	23/28	1	NM_000335.5	A1	Q14524-2

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152186

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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:

0.0000360

AC:

AN:

249826

Hom.:

AF XY:

0.0000443

AC XY:

AN XY:

135492

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000579

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000545

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000442

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000287

AC:

AN:

1461690

Hom.:

Cov.:

AF XY:

0.0000344

AC XY:

AN XY:

727126

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000288

Gnomad4 OTH exome

AF:

0.0000663

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152186

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74340

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

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:

0.0000564

Hom.:

Bravo

AF:

0.0000378

ExAC

AF:

0.0000330

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.000178

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:9

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Aug 28, 2020	In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 30244407, 32569262, 31737537) -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Jan 17, 2024	This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 1391 of the SCN5A protein (p.Gly1391Arg). This variant is present in population databases (rs780405533, gnomAD 0.006%). This missense change has been observed in individual(s) with long QT syndrome (PMID: 30244407, 31737537). ClinVar contains an entry for this variant (Variation ID: 201589). 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. -

Cardiac arrhythmia

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Dec 15, 2023	This missense variant replaces glycine with arginine at codon 1391 of the SCN5A protein. Computational prediction tools indicate that this variant's impact on protein structure and function is inconclusive. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with long QT syndrome and in her asymptomatic brother (PMID: 30244407) and in an individual suspected of being affected with long QT syndrome (PMID: 31737537). This variant has been identified in 9/249826 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	Jan 03, 2024	This missense variant replaces glycine with arginine at codon 1391 of the SCN5A protein. Computational prediction tools indicate that this variant's impact on protein structure and function is inconclusive. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with long QT syndrome and in her asymptomatic brother (PMID: 30244407) and in an individual suspected of being affected with long QT syndrome (PMID: 31737537). This variant has been identified in 9/249826 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. -

Dilated cardiomyopathy 1E;C1859062:Long QT syndrome 3;C2751898:Ventricular fibrillation, paroxysmal familial, type 1;C3151464:Atrial fibrillation, familial, 10;C4551804:Brugada syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

New York Genome Center

Sep 21, 2022

The c.4171G>A variant in SCN5A has previously been reported in individuals affected with long QT syndrome [PMID:30244407, 31737537] and in a related asymptomatic individual, both of which carried another variant in the KCNH2 [PMID:30244407]. The c.4171G>A variant has been deposited in ClinVar [ClinVar ID:201589] as a Variant of Uncertain Significance and is observed in 25 alleles (0.0031% minor allele frequency with 0 homozygotes) in population databases (gnomADv2.1.1 and v3.1.2, TOPMed Freeze 8, All of Us), suggesting it is not a common benign variant in the populations represented in those databases. The c.4171G>A variant in SCN5A is located in exon 23 of this 28-exon gene and predicted to replace an evolutionarily conserved glycine amino acid with arginine at position 1391 in the transmembrane DIII-repeat region of the protein [Uniprot, PMID:30364184]. In silico predictions are inconclusive of p. (Gly1391Arg) the variant's effect [(CADD v1.6 =36, REVEL = 0.633)]; however, there are no functional studies to support or refute these predictions. Variants nearby p.(Gly1391) residue within the DIII-repeat region have been reported in the literature [PMID: 20129283] and ClinVar [ClinVar ID: 9395] in individuals with Brugada syndrome. Based on available evidence this c.4171G>A p.(Gly1391Arg) variant identified in SCN5A is classified as a Variant of Uncertain Significance. -

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

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Feb 09, 2022

- -

Brugada syndrome

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Molecular Genetics Laboratory, BC Children's and BC Women's Hospitals

Aug 14, 2019

- -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 16, 2020

The p.G1391R variant (also known as c.4171G>A), located in coding exon 22 of the SCN5A gene, results from a G to A substitution at nucleotide position 4171. The glycine at codon 1391 is replaced by arginine, an amino acid with dissimilar properties. This alteration was detected in an individual with long QT syndrome as well as in her asymptomatic older brother, both of whom also carried the KCNH2 p.D803Y (c.2407G>T) (Szperl M et al. J. Appl. Genet., 2018 Nov;59:463-469). 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. -

Long QT syndrome 3

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

May 04, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.28

CardioboostArm

Benign

0.0080

CardioboostCm

Benign

0.014

BayesDel_addAF

Pathogenic

0.29

BayesDel_noAF

Pathogenic

0.35

Cadd

Benign

Dann

Uncertain

1.0

Eigen

Benign

-0.13

Eigen_PC

Benign

-0.24

FATHMM_MKL

Benign

0.42

M_CAP

Pathogenic

0.48

MetaRNN

Pathogenic

0.85

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

MetaSVM

Pathogenic

1.0

MutationTaster

Benign

1.0

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

PrimateAI

Uncertain

0.64

PROVEAN

Uncertain

-2.8

D;D;D;D;N;D;N;N;N

REVEL

Uncertain

0.63

Sift

Uncertain

0.025

D;D;D;D;T;D;D;T;T

Sift4G

Benign

0.26

T;T;T;T;T;T;T;T;T

Polyphen

0.99

D;D;.;D;.;P;D;.;.

Vest4

0.77

MutPred

0.64

Gain of loop (P = 0.069);.;Gain of loop (P = 0.069);Gain of loop (P = 0.069);.;Gain of loop (P = 0.069);.;.;.;

MVP

0.95

MPC

1.6

ClinPred

0.18

GERP RS

4.2

Varity_R

0.22

gMVP

0.95

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.090

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

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