rs1553693632

Positions:

• chr3-38554368-C-T

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.4721G>A​(p.Cys1574Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,742 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: 31)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: SCN5A NM_000335.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• 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]

SCN5A (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a helix (size 27) in uniprot entity SCN5A_HUMAN there are 9 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, 0.942

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.4724G>A	p.Cys1575Tyr	missense_variant	27/28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.4721G>A	p.Cys1574Tyr	missense_variant	27/28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.4724G>A	p.Cys1575Tyr	missense_variant	27/28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.4721G>A	p.Cys1574Tyr	missense_variant	27/28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461742 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727160

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 31

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Brugada syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

in vitro;research

Roden Lab, Vanderbilt University Medical Center

-

We classified this variant using data from the calibrated functional assay 'ParSE-seq' (PMID: 37732247), population data, and in silico data within the ACMG v3 framework (PMID: 25741868)The SCN5A variant, 3-38554368-C-T was evaluated for association with the loss-of-function condition Brugada Syndrome.This Variant had an AF of 0 in gnomAD v3The in silico predictor SpliceAI scored the variant as 0.3016; normal <0.2, likely damaging >0.5.Using the functional RNA-splicing assay, ParSE-seq, the variant was evaluated to have a strong negative impact on splicing (PS3_strong) following the Brnich et al. calibration framework (PMID: 31892348). In aggregate, we therefore classify this variant as VUS using these collective data. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 09, 2022

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 sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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. ClinVar contains an entry for this variant (Variation ID: 532081). This variant has not been reported in the literature in individuals affected with SCN5A-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces cysteine, which is neutral and slightly polar, with tyrosine, which is neutral and polar, at codon 1575 of the SCN5A protein (p.Cys1575Tyr). -

Cardiac arrhythmia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Oct 09, 2019

This missense variant replaces cysteine with tyrosine at codon 1575 of the SCN5A protein. Computational prediction tool suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold ≥0.7, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has not been reported in individuals affected with cardiovascular disorders in the literature. 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	0.93
CardioboostCm	Uncertain	0.90
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.99	.;.;.;.;.;D;.;.
Eigen	Pathogenic	0.70
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.86	.;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.4	.;.;.;.;.;H;.;.
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-7.6	D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0060	D;D;D;D;D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D
Polyphen		0.99	D;D;.;D;.;D;.;.
Vest4		0.96
MutPred		0.67		.;.;Loss of methylation at K1578 (P = 0.0651);.;.;Loss of methylation at K1578 (P = 0.0651);.;.;
MVP		0.71
MPC		1.8
ClinPred		1.0	D
GERP RS		3.7
Varity_R		0.97
gMVP		0.97

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.28		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.28		Position offset: 7

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

Publications

LitVar

Other links and lift over

dbSNP: rs1553693632; hg19: chr3-38595859;