NM_001099404.2:c.871A>C

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2PP2PP3_Moderate

The NM_001099404.2(SCN5A):c.871A>C(p.Asn291His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000026 in 1,613,728 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. N291S) has been classified as Likely benign.

Frequency

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

Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

SCN5A
NM_001099404.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5O:1

Conservation

PhyloP100: 3.43

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 Uncertain_significance. Variant got 5 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in the SCN5A gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 99 curated pathogenic missense variants (we use a threshold of 10). The gene has 60 curated benign missense variants. Gene score misZ: 2.7504 (below the threshold of 3.09). Trascript score misZ: 4.7729 (above the threshold of 3.09). GenCC associations: The gene is linked to 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, 0.846

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2 link	c.871A>C	p.Asn291His	missense_variant	Exon 7 of 28	ENST00000413689.6	NP_001092874.1	Q14524H9KVD2
SCN5A	NM_000335.5 link	c.871A>C	p.Asn291His	missense_variant	Exon 7 of 28	ENST00000423572.7	NP_000326.2	Q14524-2Q86V90

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6 link	c.871A>C	p.Asn291His	missense_variant	Exon 7 of 28	5	NM_001099404.2	ENSP00000410257.1		H9KVD2
SCN5A	ENST00000423572.7 link	c.871A>C	p.Asn291His	missense_variant	Exon 7 of 28	1	NM_000335.5	ENSP00000398266.2		Q14524-2

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152264

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000803

AC:

AN:

249126

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135148

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000177

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000267

AC:

AN:

1461464

Hom.:

Cov.:

AF XY:

0.0000248

AC XY:

AN XY:

727026

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000324

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152264

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74394

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000282

Hom.:

Bravo

AF:

0.0000151

EpiCase

AF:

0.0000545

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Nov 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces asparagine, which is neutral and polar, with histidine, which is basic and polar, at codon 291 of the SCN5A protein (p.Asn291His). This variant is present in population databases (rs36210420, gnomAD 0.002%). This missense change has been observed in individual(s) with SCN5A-related conditions (PMID: 17161064, 30079003, 34930020). ClinVar contains an entry for this variant (Variation ID: 68051). 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 does not substantially affect SCN5A function (PMID: 34930020). 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 13, 2017

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

A variant of uncertain significance has been identified in the SCN5A gene. The N291H variant has previously been reported as a polymorphism" in an individual of European ancestry with torsades de pointes (Mank-Seymour et al., 2006). In addition, this variant has been observed in other unrelated individuals referred for cardiac genetic testing at GeneDx; however, segregation data is insufficient to determine the pathogenicity of this variant. In silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. Nevertheless, the N291H variant is a semi-conservative amino acid substitution, which may impact secondary protein structure as these residues differ in some properties. This substitution occurs at a position that is conserved in mammals. Furthermore, the N291H variant was not observed in approximately 6,400 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations.Therefore, based on the currently available information, it is unclear whether this variant is pathogenic or benign." -

Cardiac arrhythmia

Uncertain:2

Jul 05, 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 asparagine with histidine at codon 291 of the SCN5A protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). A functional study has shown that this variant has no significant impact on channel peak current density (PMID: 34930020). This variant has been reported in an individual affected with torsades de pointes (PMID: 17161064) and in another individual noted with atrial fibrillation, long QT syndrome, and syncope from a population screening study (PMID: 34930020). This variant has been identified in 3/280536 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. -

Mar 10, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Cardiovascular phenotype

Uncertain:1

Sep 30, 2020

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.871A>C (p.N291H) alteration is located in exon 7 (coding exon 6) of the SCN5A gene. This alteration results from a A to C substitution at nucleotide position 871, causing the asparagine (N) at amino acid position 291 to be replaced by a histidine (H). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Torsades de pointes

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 torsades de pointes in the following publications (PMID:17161064). 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

0.22

CardioboostCm

Benign

0.032

BayesDel_addAF

Uncertain

0.16

BayesDel_noAF

Uncertain

0.0

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Pathogenic

0.81

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

Eigen

Uncertain

0.54

Eigen_PC

Uncertain

0.50

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.80

.;T;T;T;T;T;T;.;T

M_CAP

Pathogenic

0.32

MetaRNN

Pathogenic

0.85

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

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.1

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

PrimateAI

Uncertain

0.57

PROVEAN

Benign

-1.6

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

REVEL

Uncertain

0.59

Sift

Benign

0.16

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

Sift4G

Benign

0.56

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

Polyphen

0.95

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

Vest4

0.68

MutPred

0.55

Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);

MVP

0.92

MPC

1.1

ClinPred

0.62

GERP RS

5.3

Varity_R

0.12

gMVP

0.88

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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