rs373156650

Variant names:

• chr3-38566589-A-T
• rs373156650
• NM_001099404.2:c.3667-7T>A

Variant summary

Our verdict is Benign. The variant received -9 ACMG points: 0P and 9B. BP4_Strong BP6 BS1

The NM_001099404.2(SCN5A):​c.3667-7T>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000781 in 1,613,418 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000046 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000081 (0 hom.)
• Consequence: SCN5A NM_001099404.2 splice_region, intron
• Scores: Splicing: ADA: 0.1027
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:7
• Conservation: PhyloP100: 0.787
• Publications: 0 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: Benign. The variant received -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.76).
• BP6: Variant 3-38566589-A-T is Benign according to our data. Variant chr3-38566589-A-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 139059.
• BS1: Variant frequency is greater than expected in population mid. GnomAdExome4 allele frequency = 0.0000814 (119/1461198) while in subpopulation MID AF = 0.0026 (15/5762). AF 95% confidence interval is 0.0016. There are 0 homozygotes in GnomAdExome4. There are 60 alleles in the male GnomAdExome4 subpopulation. Median coverage is 31. This position passed quality control check.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.3667-7T>A		splice_region_variant, intron_variant	Intron 20 of 27	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.3664-7T>A		splice_region_variant, intron_variant	Intron 20 of 27	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.3667-7T>A		splice_region_variant, intron_variant	Intron 20 of 27	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.3664-7T>A		splice_region_variant, intron_variant	Intron 20 of 27	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes AF: 0.0000460 AC: 7 AN: 152220 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000103

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000802 AC: 20 AN: 249358 AF XY: 0.0000665

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000174

Gnomad ASJ exome AF: 0.0000994

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000885

Gnomad OTH exome AF: 0.000495

GnomAD4 exome AF: 0.0000814 AC: 119 AN: 1461198 Hom.: 0 Cov.: 31 AF XY: 0.0000825 AC XY: 60 AN XY: 726910

African (AFR) AF: 0.0000597 AC: 2 AN: 33474

American (AMR) AF: 0.000157 AC: 7 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39678

South Asian (SAS) AF: 0.0000232 AC: 2 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53212

Middle Eastern (MID) AF: 0.00260 AC: 15 AN: 5762

European-Non Finnish (NFE) AF: 0.0000783 AC: 87 AN: 1111638

Other (OTH) AF: 0.0000829 AC: 5 AN: 60342

GnomAD4 genome AF: 0.0000460 AC: 7 AN: 152220 Hom.: 0 Cov.: 33 AF XY: 0.0000538 AC XY: 4 AN XY: 74372

African (AFR) AF: 0.00 AC: 0 AN: 41464

American (AMR) AF: 0.00 AC: 0 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5200

South Asian (SAS) AF: 0.00 AC: 0 AN: 4822

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.000103 AC: 7 AN: 68034

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.000203 Hom.: 0

Bravo AF: 0.0000378

EpiCase AF: 0.0000545

EpiControl AF: 0.000237

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:7

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not specified Benign:2

Apr 29, 2025

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

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: SCN5A c.3667-7T>A alters a non-conserved nucleotide located at a position not widely known to affect splicing. Consensus agreement among computation tools predict no significant impact on normal splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 8e-05 in 249358 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in SCN5A causing Arrhythmia (8e-05 vs 0.0001), allowing no conclusion about variant significance. To our knowledge, no occurrence of c.3667-7T>A in individuals affected with Arrhythmia and no experimental evidence demonstrating its impact on protein function have been reported. ClinVar contains an entry for this variant (Variation ID: 139059). Based on the evidence outlined above, the variant was classified as likely benign. -

May 16, 2014

GeneDx

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

not provided Benign:2

Jan 01, 2025

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

SCN5A: BP4, BS2 -

Jan 22, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiac arrhythmia Benign:2

Dec 21, 2018

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 13, 2023

All of Us Research Program, National Institutes of Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiovascular phenotype Uncertain:1

Nov 12, 2016

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.3667-7T>A intronic alteration consists of a T to A substitution 7 nucleotides before coding exon 20 in the SCN5A gene. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Brugada syndrome 1 Benign:1

-

Roden Lab, Vanderbilt University Medical Center

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: in vitro;research

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, 3-38566589-A-T was evaluated for association with the loss-of-function condition Brugada Syndrome.This Variant had an AF of 0.000046 in gnomAD v3The in silico predictor SpliceAI scored the variant as 0.01; normal <0.2, likely damaging >0.5.Using the functional RNA-splicing assay, ParSE-seq, the variant was evaluated to have no impact on splicing (BS3_strong) following the Brnich et al. calibration framework (PMID: 31892348). We do not apply benign splicing functional data to missense variants. In aggregate, we therefore classify this variant as LB using these collective data. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.76
CADD	Benign	10
DANN	Benign	0.68
PhyloP100		0.79
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.10
dbscSNV1_RF	Benign	0.41
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

Other links and lift over

dbSNP: rs373156650; hg19: chr3-38608080;