NM_001099404.2:c.3391-7T>C

Variant names:

• chr3-38576788-A-G
• rs41310769
• NM_001099404.2:c.3391-7T>C

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.3391-7T>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000349 in 1,606,816 control chromosomes in the GnomAD database, including 1 homozygotes. 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 0.000092 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000029 (1 hom.)
• Consequence: SCN5A NM_001099404.2 splice_region, intron
• Scores: Splicing: ADA: 0.0001074
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4 B:9
• Conservation: PhyloP100: 0.0490
• 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=-0.89).
• BP6: Variant 3-38576788-A-G is Benign according to our data. Variant chr3-38576788-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 345118.
• BS1: Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.000092 (14/152166) while in subpopulation EAS AF = 0.0027 (14/5194). AF 95% confidence interval is 0.00163. There are 0 homozygotes in GnomAd4. There are 10 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.3391-7T>C		splice_region_variant, intron_variant	Intron 18 of 27	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.3388-7T>C		splice_region_variant, intron_variant	Intron 18 of 27	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.3391-7T>C		splice_region_variant, intron_variant	Intron 18 of 27	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.3388-7T>C		splice_region_variant, intron_variant	Intron 18 of 27	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes AF: 0.0000920 AC: 14 AN: 152166 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: 0.00270

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.000277 AC: 66 AN: 237952 AF XY: 0.000271

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00381

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000289 AC: 42 AN: 1454650 Hom.: 1 Cov.: 30 AF XY: 0.0000304 AC XY: 22 AN XY: 722578

African (AFR) AF: 0.00 AC: 0 AN: 33406

American (AMR) AF: 0.00 AC: 0 AN: 43862

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25944

East Asian (EAS) AF: 0.00101 AC: 40 AN: 39528

South Asian (SAS) AF: 0.00 AC: 0 AN: 84648

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52994

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5752

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1108440

Other (OTH) AF: 0.0000333 AC: 2 AN: 60076

GnomAD4 genome AF: 0.0000920 AC: 14 AN: 152166 Hom.: 0 Cov.: 33 AF XY: 0.000135 AC XY: 10 AN XY: 74330

African (AFR) AF: 0.00 AC: 0 AN: 41448

American (AMR) AF: 0.00 AC: 0 AN: 15274

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

East Asian (EAS) AF: 0.00270 AC: 14 AN: 5194

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10616

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68016

Other (OTH) AF: 0.00 AC: 0 AN: 2088

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.000140

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4 Benign:9

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Brugada syndrome 1 Benign:2

-

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, 3-38576788-A-G was evaluated for association with the loss-of-function condition Brugada Syndrome.This Variant had an AF of 0.000092 in gnomAD v3The in silico predictor SpliceAI scored the variant as 0; 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. -

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Cardiac arrhythmia Benign:2

Nov 08, 2018

Color Diagnostics, LLC DBA Color Health

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dec 13, 2023

All of Us Research Program, National Institutes of Health

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Dilated cardiomyopathy 1E Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Ventricular fibrillation, paroxysmal familial, type 1 Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Progressive familial heart block, type 1A Uncertain:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Congenital long QT syndrome Uncertain:1

Jun 14, 2016

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified Benign:1

Sep 05, 2017

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. -

Sick sinus syndrome 1 Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Brugada syndrome Benign:1

Feb 26, 2020

Molecular Genetics Laboratory, BC Children's and BC Women's Hospitals

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

not provided Benign:1

Jan 30, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Long QT syndrome 3 Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.89
CADD	Benign	4.3
DANN	Benign	0.51
PhyloP100		0.049
Mutation Taster		=100/0	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00011
dbscSNV1_RF	Benign	0.0
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

Other links and lift over

dbSNP: rs41310769; hg19: chr3-38618279;