3-38550764-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1PM2PP2

The NM_000335.5(SCN5A):c.5605G>A(p.Ala1869Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,814 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

SCN5A
NM_000335.5 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 3.40

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.

PM1

In a region_of_interest Interaction with FGF13 (size 62) in uniprot entity SCN5A_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_000335.5

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: 4.8279 (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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2 link	c.5608G>A	p.Ala1870Thr	missense_variant	Exon 28 of 28	ENST00000413689.6	NP_001092874.1	Q14524H9KVD2
SCN5A	NM_000335.5 link	c.5605G>A	p.Ala1869Thr	missense_variant	Exon 28 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.5608G>A	p.Ala1870Thr	missense_variant	Exon 28 of 28	5	NM_001099404.2	ENSP00000410257.1		H9KVD2
SCN5A	ENST00000423572.7 link	c.5605G>A	p.Ala1869Thr	missense_variant	Exon 28 of 28	1	NM_000335.5	ENSP00000398266.2		Q14524-2

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152116

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:

0.000193

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:

0.00000802

AC:

AN:

249268

Hom.:

AF XY:

0.00000740

AC XY:

AN XY:

135226

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:

0.0000157

AC:

AN:

1461698

Hom.:

Cov.:

AF XY:

0.0000206

AC XY:

AN XY:

727132

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

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:

0.0000180

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152116

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74306

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000565

Hom.:

Bravo

AF:

0.0000113

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Aug 14, 2023

Revvity Omics, Revvity

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 22, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1870 of the SCN5A protein (p.Ala1870Thr). This variant is present in population databases (rs794728939, gnomAD 0.002%). This missense change has been observed in individual(s) with clinical features of SCN5A-related conditions (PMID: 23631430). ClinVar contains an entry for this variant (Variation ID: 201595). 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. -

Cardiac arrhythmia

Uncertain:2

Sep 23, 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 alanine with threonine at codon 1870 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). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual referred for long QT syndrome genetic testing (PMID: 23631430). This variant has been identified in 2/249268 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. -

Feb 13, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Cardiovascular phenotype

Uncertain:1

Mar 30, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.A1870T variant (also known as c.5608G>A), located in coding exon 27 of the SCN5A gene, results from a G to A substitution at nucleotide position 5608. The alanine at codon 1870 is replaced by threonine, an amino acid with similar properties. This variant has been detected in a long QT syndrome genetic testing cohort, and in a cohort not selected for the presence of cardiovascular disease; however, clinical details were limited (Lieve KV et al. Genet Test Mol Biomarkers, 2013 Jul;17:553-61; Diebold I et al. Hum Mutat. 2020 May;41(5):1025-1032). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Long QT syndrome 3

Uncertain:1

Neuberg Centre For Genomic Medicine, NCGM

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The missense variant p.A1869T in SCN5A (NM_000335.5) has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The p.A1869T variant is observed in 2/1,13,022 (0.0018%) alleles from individuals of European (Non-Finnish) background in gnomAD Exomes and is novel (not in any individuals) in 1000 Genomes. There is a small physicochemical difference between alanine and threonine, which is not likely to impact secondary protein structure as these residues share similar properties.The variant has been reported to ClinVar as Uncertain Significance. For these reasons, this variant has been classified as Uncertain Significance. Disease causing variants in SCN5A have also been reported in Brugada syndrome,Heart Block, cardiomyopathy and ventricular fibrillation -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.10

CardioboostCm

Benign

0.0070

BayesDel_addAF

Pathogenic

0.18

BayesDel_noAF

Uncertain

0.030

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.59

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

Eigen

Benign

0.15

Eigen_PC

Uncertain

0.25

FATHMM_MKL

Uncertain

0.92

LIST_S2

Uncertain

0.86

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

M_CAP

Pathogenic

0.70

MetaRNN

Uncertain

0.50

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

MetaSVM

Pathogenic

0.91

MutationAssessor

Benign

0.89

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

PrimateAI

Uncertain

0.70

PROVEAN

Benign

-1.6

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

REVEL

Uncertain

0.61

Sift

Benign

0.17

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

Sift4G

Benign

0.49

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

Polyphen

0.21

B;B;.;B;.;B;D;.;.

Vest4

0.80

MutPred

0.21

.;.;Gain of helix (P = 0.0696);.;.;Gain of helix (P = 0.0696);.;.;.;

MVP

0.73

MPC

1.4

ClinPred

0.81

GERP RS

4.8

Varity_R

0.46

gMVP

0.87

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