NM_001099404.2:c.2822C>G

Variant names:

• chr3-38581337-G-C
• rs1296243690
• NM_001099404.2:c.2822C>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM5 PP3_Moderate

The NM_001099404.2(SCN5A):​c.2822C>G​(p.Ser941Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000414 in 1,450,172 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/24 in silico tools predict a damaging 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. S941N) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: SCN5A NM_001099404.2 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 10.0
• Publications: 1 publications found

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 Gene-Disease associations (from GenCC):

• Brugada syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Brugada syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1E

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• familial long QT syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• long QT syndrome 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• sick sinus syndrome 1

  Inheritance: AD, AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
• progressive familial heart block, type 1A

  Inheritance: SD, AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Genomics England PanelApp
• atrial standstill

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial atrial fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial sick sinus syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• paroxysmal familial ventricular fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• progressive familial heart block

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• catecholaminergic polymorphic ventricular tachycardia

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• short QT syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-38581337-GA-TT is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 9384.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.916

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.2822C>G	p.Ser941Cys	missense_variant	Exon 17 of 28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.2822C>G	p.Ser941Cys	missense_variant	Exon 17 of 28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.2822C>G	p.Ser941Cys	missense_variant	Exon 17 of 28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.2822C>G	p.Ser941Cys	missense_variant	Exon 17 of 28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000414 AC: 6 AN: 1450172 Hom.: 0 Cov.: 36 AF XY: 0.00000278 AC XY: 2 AN XY: 718690

African (AFR) AF: 0.00 AC: 0 AN: 33190

American (AMR) AF: 0.00 AC: 0 AN: 44248

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25938

East Asian (EAS) AF: 0.00 AC: 0 AN: 39348

South Asian (SAS) AF: 0.00 AC: 0 AN: 85742

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53270

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5730

European-Non Finnish (NFE) AF: 0.00000544 AC: 6 AN: 1102904

Other (OTH) AF: 0.00 AC: 0 AN: 59802

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Cardiovascular phenotype Uncertain:1

Sep 27, 2017

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S941C variant (also known as c.2822C>G), located in coding exon 16 of the SCN5A gene, results from a C to G substitution at nucleotide position 2822. The serine at codon 941 is replaced by cysteine, an amino acid with dissimilar properties. An alternate amino acid this position, p.S941N (c.2821_2822delTCinsAA), was reported to be de novo in a child with ventricular fibrillation, torsade de pointes, and prolonged QT intervals (Schwartz PJ et al. N. Engl. J. Med., 2000 Jul;343:262-7; Ruan Y et al. Circulation, 2007 Sep;116:1137-44). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia Uncertain:1

May 14, 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 serine with cysteine at codon 941 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 not been reported in individuals affected with SCN5A-related disorders in the literature. This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). A different variant occurring at the same codon, p.Ser941Asn, is known to be pathogenic (Clinvar variation ID 9384), indicating that serine at this position is important for SCN5A protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.76
CardioboostArm	Uncertain	0.50
CardioboostCm	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.56
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.98	.;.;.;.;.;D;.;.;.
Eigen	Pathogenic	0.99
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.96	.;D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.88	D
MetaRNN	Pathogenic	0.92	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.1	.;H;.;.;.;H;.;.;.
PhyloP100		10
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-4.9	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.92
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.014	D;D;D;D;D;D;D;D;D
Polyphen		1.0	D;D;.;D;.;D;D;.;.
Vest4		0.88
MutPred		0.53		Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);Loss of disorder (P = 0.007);
MVP		0.98
MPC		1.1
ClinPred		1.0	D
GERP RS		4.6
Varity_R		0.83
gMVP		0.87
Mutation Taster		=3/97	disease causing

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

Other links and lift over

dbSNP: rs1296243690; hg19: chr3-38622828;