rs199473257

Variant names:

• chr3-38555756-C-T
• rs199473257
• NM_001099404.2:c.4442G>A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP2 PP3 PP5_Moderate

The NM_000335.5(SCN5A):​c.4439G>A​(p.Gly1480Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: SCN5A NM_000335.5 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 7.86

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 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_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.
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 3-38555756-C-T is Pathogenic according to our data. Variant chr3-38555756-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 67893.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr3-38555756-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.4442G>A	p.Gly1481Glu	missense_variant	Exon 26 of 28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.4439G>A	p.Gly1480Glu	missense_variant	Exon 26 of 28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.4442G>A	p.Gly1481Glu	missense_variant	Exon 26 of 28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.4439G>A	p.Gly1480Glu	missense_variant	Exon 26 of 28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Jun 28, 2023

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Reported in association with an SCN5A-related disorder; however, no detailed clinical information was provided (Tester et al., 2005); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on splicing and on protein structure/function; This variant is associated with the following publications: (PMID: 15840476, 5840476, 22581653) -

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:15840476;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	Pathogenic	0.69
CardioboostCm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.54	D
BayesDel_noAF	Pathogenic	0.54
CADD	Pathogenic	34
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.86	.;.;.;.;.;D;.;.;.
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.54
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.93	.;D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.85	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.0	.;.;.;.;.;M;.;.;.
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-5.3	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.85
Sift	Uncertain	0.0010	D;D;D;D;D;D;D;D;D
Sift4G	Benign	0.15	T;T;T;T;T;T;T;T;T
Vest4		0.84
MutPred		0.45		.;.;.;.;Gain of solvent accessibility (P = 0.0171);.;.;Gain of solvent accessibility (P = 0.0171);Gain of solvent accessibility (P = 0.0171);
MVP		0.86
MPC		0.94
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.73
gMVP		0.92

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.56		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.56		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs199473257; hg19: chr3-38597247; COSMIC: COSV105205396; COSMIC: COSV105205396;