NM_001099404.2:c.4459A>C

Variant names:

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP2PP3

The NM_001099404.2(SCN5A):c.4459A>C(p.Met1487Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000805 in 1,613,930 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 (★★).

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 31)

Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

SCN5A
NM_001099404.2 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6O:1

Conservation

PhyloP100: 7.97

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 6 ACMG points.

PM1

In a topological_domain Cytoplasmic (size 62) in uniprot entity SCN5A_HUMAN there are 15 pathogenic changes around while only 1 benign (94%) in NM_001099404.2

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, 0.759

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2 link	c.4459A>C	p.Met1487Leu	missense_variant	Exon 26 of 28	ENST00000413689.6	NP_001092874.1	Q14524H9KVD2
SCN5A	NM_000335.5 link	c.4456A>C	p.Met1486Leu	missense_variant	Exon 26 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.4459A>C	p.Met1487Leu	missense_variant	Exon 26 of 28	5	NM_001099404.2	ENSP00000410257.1		H9KVD2
SCN5A	ENST00000423572.7 link	c.4456A>C	p.Met1486Leu	missense_variant	Exon 26 of 28	1	NM_000335.5	ENSP00000398266.2		Q14524-2

Frequencies

GnomAD3 genomes

AF:

0.0000460

AC:

AN:

152106

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000169

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251464

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135910

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000410

AC:

AN:

1461824

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727224

show subpopulations

Gnomad4 AFR exome

AF:

0.000149

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000460

AC:

AN:

152106

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74308

show subpopulations

Gnomad4 AFR

AF:

0.000169

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:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000132

Hom.:

Bravo

AF:

0.0000642

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:3

Dec 12, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 1487 of the SCN5A protein (p.Met1487Leu). This variant is present in population databases (rs199473258, gnomAD 0.01%). This missense change has been observed in individual(s) with long QT syndrome and in an individual who suffered sudden unexplained death (PMID: 19716085, 29247119). ClinVar contains an entry for this variant (Variation ID: 67895). 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 tolerated. 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 23, 2021

AiLife Diagnostics, AiLife Diagnostics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 06, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Identified in a patient referred for long QT syndrome testing, however, no clinical information was provided (PMID: 19716085); Identified in two cases with sudden unexpected death, however, detailed clinical and segregation information was not available (PMID: 24631775, 29247119); Not observed at significant frequency in large population cohorts (gnomAD); 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: 32569262, 29247119, 28316956, 19716085, 24631775, 22581653, 30669290) -

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

Nov 03, 2021

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiovascular phenotype

Uncertain:1

Sep 30, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.4459A>C (p.M1487L) alteration is located in exon 26 (coding exon 25) of the SCN5A gene. This alteration results from a A to C substitution at nucleotide position 4459, causing the methionine (M) at amino acid position 1487 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia

Uncertain:1

May 07, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces methionine with leucine at codon 1487 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). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in one individual referred for long QT syndrome genetic test (PMID: 19716085) and one case of sudden unexplained death (PMID: 24631775, 29247119). This variant has been identified in 3/282820 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. -

Congenital long QT 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 Long QT syndrome in the following publications (PMID:19716085). 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

Uncertain

0.40

CardioboostCm

Uncertain

0.31

BayesDel_addAF

Pathogenic

0.32

BayesDel_noAF

Pathogenic

0.41

CADD

Uncertain

DANN

Benign

0.97

DEOGEN2

Uncertain

0.76

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

Eigen

Benign

0.15

Eigen_PC

Uncertain

0.27

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.91

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

M_CAP

Pathogenic

0.46

MetaRNN

Pathogenic

0.76

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

MetaSVM

Pathogenic

0.86

MutationAssessor

Uncertain

2.0

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

PrimateAI

Pathogenic

0.92

PROVEAN

Uncertain

-2.8

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

REVEL

Pathogenic

0.81

Sift

Uncertain

0.0010

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

Sift4G

Benign

0.27

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

Polyphen

0.0020

B;B;.;B;.;B;B;.;.

Vest4

0.88

MutPred

0.84

.;.;Loss of disorder (P = 0.1149);.;.;Loss of disorder (P = 0.1149);.;.;.;

MVP

0.97

MPC

0.48

ClinPred

0.94

GERP RS

4.5

Varity_R

0.75

gMVP

0.91

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

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