3-38599026-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_000335.5(SCN5A):c.1915G>A(p.Gly639Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000305 in 1,608,342 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/25 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Synonymous variant affecting the same amino acid position (i.e. G639G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000030 ( 0 hom. )

Consequence

SCN5A
NM_000335.5 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 2.12

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 was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.2471236).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2 link	c.1915G>A	p.Gly639Arg	missense_variant	Exon 13 of 28	ENST00000413689.6	NP_001092874.1	Q14524H9KVD2
SCN5A	NM_000335.5 link	c.1915G>A	p.Gly639Arg	missense_variant	Exon 13 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.1915G>A	p.Gly639Arg	missense_variant	Exon 13 of 28	5	NM_001099404.2	ENSP00000410257.1		H9KVD2
SCN5A	ENST00000423572.7 link	c.1915G>A	p.Gly639Arg	missense_variant	Exon 13 of 28	1	NM_000335.5	ENSP00000398266.2		Q14524-2

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152174

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:

0.0000735

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000122

AC:

AN:

246566

AF XY:

0.0000149

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000557

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000180

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000302

AC:

AN:

1456168

Hom.:

Cov.:

AF XY:

0.0000235

AC XY:

AN XY:

723126

show subpopulations

Gnomad4 AFR exome

AF:

0.00

AC:

AN:

33398

Gnomad4 AMR exome

AF:

0.00

AC:

AN:

44608

Gnomad4 ASJ exome

AF:

0.00

AC:

AN:

26042

Gnomad4 EAS exome

AF:

0.0000506

AC:

AN:

39544

Gnomad4 SAS exome

AF:

0.00

AC:

AN:

86106

Gnomad4 FIN exome

AF:

0.00

AC:

AN:

53296

Gnomad4 NFE exome

AF:

0.0000361

AC:

AN:

1107418

Gnomad4 Remaining exome

AF:

0.0000167

AC:

AN:

60010

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.0000329

AC:

AN:

152174

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74350

show subpopulations

Gnomad4 AFR

AF:

0.00

AC:

AN:

Gnomad4 AMR

AF:

0.00

AC:

AN:

Gnomad4 ASJ

AF:

0.00

AC:

AN:

Gnomad4 EAS

AF:

0.00

AC:

AN:

Gnomad4 SAS

AF:

0.00

AC:

AN:

Gnomad4 FIN

AF:

0.00

AC:

AN:

Gnomad4 NFE

AF:

0.0000735

AC:

0.0000735078

AN:

0.0000735078

Gnomad4 OTH

AF:

0.00

AC:

AN:

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.0000675

Hom.:

Bravo

AF:

0.0000227

ClinVar

Significance: Conflicting classifications of pathogenicity

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

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Nov 19, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 639 of the SCN5A protein (p.Gly639Arg). This variant is present in population databases (rs199473136, gnomAD 0.006%). This missense change has been observed in individual(s) with long QT syndrome (PMID: 16922724). ClinVar contains an entry for this variant (Variation ID: 67698). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The arginine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

May 24, 2024

GeneDx

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Identified in individual(s) with long QT syndrome in published literature (PMID: 19716085); This variant is associated with the following publications: (PMID: 19716085) -

SCN5A-related disorder

Uncertain:1

Sep 08, 2022

PreventionGenetics, part of Exact Sciences

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The SCN5A c.1915G>A variant is predicted to result in the amino acid substitution p.Gly639Arg. This variant was reported in two individuals with long QT syndrome (Millat et al. 2006. PubMed ID: 16922724; Table S3, Kapplinger et al. 2009. PubMed ID: 19716085). This variant is reported in 0.0056% of alleles in individuals of East Asian descent in gnomAD (http://gnomad.broadinstitute.org/variant/3-38640517-C-T) and has conflicting interpretations of pathogenicity in ClinVar ranging from likely benign to uncertain (https://www.ncbi.nlm.nih.gov/clinvar/variation/67698/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Long QT syndrome

Uncertain:1

Apr 05, 2018

Biesecker Lab/Clinical Genomics Section, National Institutes of Health

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:research

- -

Cardiac arrhythmia

Uncertain:1

Sep 04, 2024

Color Diagnostics, LLC DBA Color Health

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This missense variant replaces glycine with arginine at codon 639 of the SCN5A protein. Computational prediction suggests that this variant may not impact protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in two individuals with long QT syndrome (PMID: 16922724, 19716085). This variant has been identified in 3/246566 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. -

Cardiovascular phenotype

Benign:1

May 08, 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. -

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

Benign

0.075

CardioboostArm

Benign

0.000058

CardioboostCm

Benign

0.012

BayesDel_addAF

Benign

0.0077

BayesDel_noAF

Uncertain

-0.060

CADD

Benign

DANN

Benign

0.90

DEOGEN2

Benign

0.41

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

Eigen

Benign

-0.70

Eigen_PC

Benign

-0.51

FATHMM_MKL

Benign

0.14

LIST_S2

Uncertain

0.87

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

M_CAP

Uncertain

0.26

MetaRNN

Benign

0.25

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

MetaSVM

Benign

-0.66

MutationAssessor

Benign

1.1

.;L;.;.;.;L;.;.;.

PrimateAI

Benign

0.34

PROVEAN

Benign

1.7

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

REVEL

Uncertain

0.49

Sift

Benign

0.79

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

Sift4G

Benign

0.61

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

Polyphen

0.0

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

Vest4

0.89

MutPred

0.68

Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);Gain of glycosylation at P637 (P = 0.1215);

MVP

0.75

MPC

0.42

ClinPred

0.15

GERP RS

1.9

Varity_R

0.036

gMVP

0.55

Mutation Taster

=0/100

disease causing

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.040

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