3-38562432-G-A

Position:

• chr3-38562432-G-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000335.5(SCN5A):​c.3943C>T​(p.Arg1315*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000686 in 1,458,534 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: SCN5A NM_000335.5 stop_gained
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 1.90

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 Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 3-38562432-G-A is Pathogenic according to our data. Variant chr3-38562432-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 496571.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-38562432-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.3946C>T	p.Arg1316*	stop_gained	22/28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.3943C>T	p.Arg1315*	stop_gained	22/28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.3946C>T	p.Arg1316*	stop_gained	22/28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.3943C>T	p.Arg1315*	stop_gained	22/28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.86e-7 AC: 1 AN: 1458534 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 725140

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:3

Likely pathogenic, no assertion criteria provided	research	Gharavi Laboratory, Columbia University	Sep 16, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Aug 26, 2020	Reported in ClinVar as likely pathogenic and pathogenic (ClinVar Variant ID# 496571; Landrum et al., 2016); Not observed in large population cohorts (Lek et al., 2016); Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 31447099, 30828344, 19561025) -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Nov 08, 2023	This sequence change creates a premature translational stop signal (p.Arg1316*) in the SCN5A gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in SCN5A are known to be pathogenic (PMID: 20129283, 22789973). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individuals with Brugada syndrome (PMID: 19561025, 30828344). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 496571). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Brugada syndrome (shorter-than-normal QT interval) Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Dec 12, 2016

Variant summary: The SCN5A c.3946C>T (p.Arg1316X) variant results in a premature termination codon, predicted to cause a truncated or absent SCN5A protein due to nonsense mediated decay. The variant of interest was not found in controls (ExAC, 1000 Gs, ESP, or published controls) and has been reported in an affected individual diagnosed with Brugada Syndrome via a publication. However, no clinical diagnostic and/or databases have cited the variant. Therefore, the variant of interest has been classified as "likely pathogenic." -

Brugada syndrome 1 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Clinical Genetics Laboratory, Region Ostergotland

Feb 18, 2021

PVS1, PM2 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	41
DANN	Uncertain	1.0
Eigen	Uncertain	0.40
Eigen_PC	Benign	0.16
FATHMM_MKL	Uncertain	0.83	D
Vest4		0.98
GERP RS		3.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs1553695764; hg19: chr3-38603923;