chr3-38587404-C-T

Position:

• chr3-38587404-C-T

Variant summary

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

The NM_001099404.2(SCN5A):​c.2432G>A​(p.Arg811His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000548 in 1,458,840 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R811C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: SCN5A NM_001099404.2 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:3
• Conservation: PhyloP100: 7.91

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 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_001099404.2
• 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 4.7729 (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, 0.98

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SCN5A	NM_001099404.2	c.2432G>A	p.Arg811His	missense_variant	15/28	ENST00000413689.6
SCN5A	NM_000335.5	c.2432G>A	p.Arg811His	missense_variant	15/28	ENST00000423572.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SCN5A	ENST00000413689.6	c.2432G>A	p.Arg811His	missense_variant	15/28	5	NM_001099404.2	P4
SCN5A	ENST00000423572.7	c.2432G>A	p.Arg811His	missense_variant	15/28	1	NM_000335.5	A1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.0000122 AC: 3 AN: 246616 Hom.: 0 AF XY: 0.0000225 AC XY: 3 AN XY: 133568

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000291

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000666

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000548 AC: 8 AN: 1458840 Hom.: 0 Cov.: 31 AF XY: 0.00000827 AC XY: 6 AN XY: 725260

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

Gnomad4 ASJ exome AF: 0.0000385

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000467

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000896 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000825 AC: 1

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:3

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1 Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jun 25, 2022	This missense change has been observed in individual(s) with clinical features of SCN5A-related conditions (PMID: 23424222). 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. Experimental studies have shown that this missense change affects SCN5A function (PMID: 23424222). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 519424). This variant is present in population databases (rs769349991, gnomAD 0.007%). This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 811 of the SCN5A protein (p.Arg811His). -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Dec 02, 2023	Not observed at significant frequency in large population cohorts (gnomAD); Published functional studies demonstrate a damaging effect through significant loss of function in peak sodium current density and alteration of inactivation and recovery from inactivation (PMID: 23424222); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 28573431, 27810048, 30662450, 34697415, 33131149, 30203441, 23424222, 35063694, 30079003) -

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

Aug 20, 2021

- -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 22, 2017

The p.R811H variant (also known as c.2432G>A), located in coding exon 14 of the SCN5A gene, results from a G to A substitution at nucleotide position 2432. The arginine at codon 811 is replaced by histidine, an amino acid with highly similar properties. This variant was detected in a proband with Brugada syndrome, who also carried the p.R620H on the second allele. The proband inherited the p.R811H alteration from his father, who was asymptomatic but had a type I Brugada pattern on ECG. The proband's brother and the proband's twin daughters carried the p.R811H alteration, and had normal ECG results. The proband's mother had the p.R620H alteration and also had a normal ECG (Calloe K et al. Circ Arrhythm Electrophysiol, 2013 Feb;6:177-84). Induced pluripotent stem cells derived from the patient's skin fibroblast showed some differences in channel activity (Liang P et al. J. Am. Coll. Cardiol., 2016 Nov;68:2086-2096). In CHO-K1 cells, this p.R811H alteration resulted in reduced peak current density and negative shift of V1/2 of inactivation, while the p.R620H alteration appeared not to affect the channel activity or modified p.R811H when expressed at 1:1 ratio (Calloe K et al. Circ Arrhythm Electrophysiol, 2013 Feb;6:177-84). 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.93
CardioboostCm	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	31
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.99	.;.;.;.;.;D;.;.;.
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.81
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.92	.;D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Pathogenic	4.4	.;H;.;.;.;H;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-4.9	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.97
Sift	Pathogenic	0.0	D;D;D;D;D;D;D;D;D
Sift4G	Uncertain	0.024	D;D;D;D;D;D;D;D;D
Polyphen		1.0	D;D;.;D;.;P;P;.;.
Vest4		0.98
MutPred		0.88		Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);Loss of MoRF binding (P = 0.0202);
MVP		1.0
MPC		0.97
ClinPred		1.0	D
GERP RS		4.3
Varity_R		0.93
gMVP		0.98

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: rs769349991; hg19: chr3-38628895; COSMIC: COSV61128055;