3-38609730-G-A

Variant names:

• chr3-38609730-G-A
• rs182050752
• NM_001099404.2:c.934+4C>T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BP6

The NM_001099404.2(SCN5A):​c.934+4C>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000114 in 1,601,066 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 0.00011 (0 hom., cov: 32)
  • Exomes 𝑓: 0.00011 (0 hom.)
• Consequence: SCN5A NM_001099404.2 splice_region, intron
• Scores: Splicing: ADA: 0.0005787
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5 B:8
• Conservation: PhyloP100: -1.37
• Publications: 2 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: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BP6: Variant 3-38609730-G-A is Benign according to our data. Variant chr3-38609730-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 463361.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001099404.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN5A	NM_001099404.2	MANE Plus Clinical	c.934+4C>T		splice_region intron	N/A	NP_001092874.1
	SCN5A	NM_000335.5	MANE Select	c.934+4C>T		splice_region intron	N/A	NP_000326.2
	SCN5A	NM_198056.3		c.934+4C>T		splice_region intron	N/A	NP_932173.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN5A	ENST00000413689.6	TSL:5 MANE Plus Clinical	c.934+4C>T		splice_region intron	N/A	ENSP00000410257.1
	SCN5A	ENST00000423572.7	TSL:1 MANE Select	c.934+4C>T		splice_region intron	N/A	ENSP00000398266.2
	SCN5A	ENST00000333535.9	TSL:1	c.934+4C>T		splice_region intron	N/A	ENSP00000328968.4

Frequencies

GnomAD3 genomes AF: 0.0000985 AC: 15 AN: 152226 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000192

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.000206

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000214 AC: 53 AN: 247310 AF XY: 0.000209

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.0000934

Gnomad NFE exome AF: 0.000447

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000115 AC: 166 AN: 1448722 Hom.: 0 Cov.: 31 AF XY: 0.0000947 AC XY: 68 AN XY: 718150

African (AFR) AF: 0.0000301 AC: 1 AN: 33220

American (AMR) AF: 0.00 AC: 0 AN: 44498

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25940

East Asian (EAS) AF: 0.00 AC: 0 AN: 39390

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 85914

European-Finnish (FIN) AF: 0.0000946 AC: 5 AN: 52838

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5740

European-Non Finnish (NFE) AF: 0.000141 AC: 155 AN: 1101440

Other (OTH) AF: 0.0000670 AC: 4 AN: 59742

GnomAD4 genome AF: 0.000105 AC: 16 AN: 152344 Hom.: 0 Cov.: 32 AF XY: 0.000134 AC XY: 10 AN XY: 74490

African (AFR) AF: 0.0000241 AC: 1 AN: 41574

American (AMR) AF: 0.00 AC: 0 AN: 15304

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

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4834

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.000206 AC: 14 AN: 68030

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.000163 Hom.: 0

Bravo AF: 0.0000680

Asia WGS AF: 0.000289 AC: 1 AN: 3478

EpiCase AF: 0.000109

EpiControl AF: 0.000178

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5 Benign:8

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Brugada syndrome 1 Uncertain:1 Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

Aug 22, 2023

Mendelics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

not provided Uncertain:1 Benign:1

Apr 08, 2021

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is associated with the following publications: (PMID: 30662450, 26332594, 27711072, 20129283)

Jan 27, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change falls in intron 7 of the SCN5A gene. It does not directly change the encoded amino acid sequence of the SCN5A protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs182050752, gnomAD 0.04%). This variant has been observed in individual(s) with Brugada syndrome or sudden cardiac death (PMID: 20129283, 37937776). ClinVar contains an entry for this variant (Variation ID: 463361). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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.

Dilated cardiomyopathy 1E Uncertain:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

Ventricular fibrillation, paroxysmal familial, type 1 Uncertain:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

Progressive familial heart block, type 1A Uncertain:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance.

not specified Benign:1

Jul 08, 2019

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.934+4C>T alters a non-conserved nucleotide located close to a canonical splice site and therefore could affect mRNA splicing, leading to a significantly altered protein sequence. 5/5 computational 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 0.00021 in 247310 control chromosomes, predominantly at a frequency of 0.00045 within the Non-Finnish European subpopulation in the gnomAD database. The variant allele was found within certain Non-Finnish European subpopulations at even higher frequencies, i.e. at a frequency of 0.00116 in the Swedish that is about 6.8 times higher than the expected maximum for a pathogenic variant in SCN5A causing Brugada Syndrome phenotype (0.00017), suggesting that the variant is a benign polymorphism found primarily in populations of Non-Finnish European origin. Though the variant, c.934+4C>T, has been reported in the literature in an individual affected with Brugada Syndrome (Kapplinger_2010), it was also reported in a healthy individual (who had no ECG signs characteristic of Brugada syndrome) (Ghouse_2017). To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two ClinVar submissions from other clinical diagnostic laboratories (evaluation after 2014) classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as likely benign.

Cardiomyopathy Benign:1

May 16, 2023

CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Sick sinus syndrome 1 Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign.

Long QT syndrome 3 Benign:1

Apr 28, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign.

Cardiovascular phenotype Benign:1

Nov 30, 2020

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Cardiac arrhythmia Benign:1

Feb 14, 2023

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	5.2
DANN	Benign	0.41
PhyloP100		-1.4
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00058
dbscSNV1_RF	Benign	0.022
SpliceAI score (max)		0.030		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: rs182050752; hg19: chr3-38651221;