3-38575334-A-G

Position:

• chr3-38575334-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_000335.5(SCN5A):​c.3626T>C​(p.Phe1209Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000959 in 1,460,528 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: not found (cov: 33)
  • Exomes 𝑓: 0.0000096 (0 hom.)
• Consequence: SCN5A NM_000335.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 9.32

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 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a transmembrane_region Helical; Name=S1 of repeat III (size 17) in uniprot entity SCN5A_HUMAN there are 4 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 gene, where missense usually causes diseases (based on misZ statistic), SCN5A. . Gene score misZ 2.7504 (greater than the threshold 3.09). Trascript score misZ 4.8279 (greater than threshold 3.09). GenCC has associacion of gene with 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, 0.946

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.3629T>C	p.Phe1210Ser	missense_variant	20/28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.3626T>C	p.Phe1209Ser	missense_variant	20/28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.3629T>C	p.Phe1210Ser	missense_variant	20/28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.3626T>C	p.Phe1209Ser	missense_variant	20/28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000959 AC: 14 AN: 1460528 Hom.: 0 Cov.: 31 AF XY: 0.0000110 AC XY: 8 AN XY: 726410

Gnomad4 AFR exome AF: 0.00

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: 0.0000117

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jul 23, 2022	ClinVar contains an entry for this variant (Variation ID: 201498). 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. This missense change has been observed in individual(s) with SCN5A-related conditions (PMID: 30059973). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces phenylalanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 1210 of the SCN5A protein (p.Phe1210Ser). -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	Nov 13, 2018	Not observed in large population cohorts (Lek et al., 2016; McVean et al., 2012; Exome Variant Server); In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; Reported as a variant of uncertain significance in ClinVar but additional evidence is not available (ClinVar SCV000545041.2; Landrum et al., 2016); Identified in several asymptomatic relatives of an individual referred for sudden cardiac arrest/arrhythmia genetic testing at GeneDx; Identified in two asymptomatic relatives of unexplained cardiac arrest survivors (Steinberg et al., 2016); This variant is associated with the following publications: (PMID: 30059973, 27635072) -

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

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Jul 07, 2021

- -

Cardiac arrhythmia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Aug 13, 2024

This missense variant replaces phenylalanine with serine at codon 1210 of the SCN5A protein. This variant is found within the highly conserved transmembrane domain DIII (a.a. 1207-1466). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with Brugada syndrome and long QT syndrome (PMID: 32893267). 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 a survivor of unexplained cardiac arrest as well as in two asymptomatic relatives in the family (PMID: 27635072). This variant has not been identified 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
CardioboostCm	Uncertain	0.77
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	.;.;.;.;.;D;.;.;.
Eigen	Pathogenic	0.71
Eigen_PC	Pathogenic	0.67
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.93	.;D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.77	D
MetaRNN	Pathogenic	0.95	D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.79	D
MutationAssessor	Pathogenic	3.2	.;.;.;.;.;M;.;.;.
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-7.5	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.035	D;D;D;D;D;D;D;D;D
Polyphen		0.87	P;D;.;P;.;P;P;.;.
Vest4		0.91
MutPred		0.73		Gain of glycosylation at F1210 (P = 0.0383);.;Gain of glycosylation at F1210 (P = 0.0383);Gain of glycosylation at F1210 (P = 0.0383);.;Gain of glycosylation at F1210 (P = 0.0383);.;.;.;
MVP		0.96
MPC		1.5
ClinPred		1.0	D
GERP RS		4.3
Varity_R		0.94
gMVP		0.93

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

Other links and lift over

dbSNP: rs794728875; hg19: chr3-38616825;