3-38550355-G-C

Position:

• chr3-38550355-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 5P and 2B. PM2 PM5 PP2 BP4_Moderate

The NM_000335.5(SCN5A):​c.6014C>G​(p.Pro2005Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000506 in 1,384,538 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P2005A) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000051 (0 hom.)
• Consequence: SCN5A NM_000335.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:9 O:1
• Conservation: PhyloP100: 3.36

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr3-38550356-G-C is described in Lovd as [Likely_pathogenic].
• 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.
• BP4: Computational evidence support a benign effect (MetaRNN=0.17461577).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.6017C>G	p.Pro2006Arg	missense_variant	28/28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.6014C>G	p.Pro2005Arg	missense_variant	28/28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.6017C>G	p.Pro2006Arg	missense_variant	28/28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.6014C>G	p.Pro2005Arg	missense_variant	28/28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000506 AC: 7 AN: 1384538 Hom.: 0 Cov.: 31 AF XY: 0.00000590 AC XY: 4 AN XY: 678384

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000654

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:9 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Brugada syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Mar 30, 2018

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. -

Dilated cardiomyopathy 1E Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Mar 30, 2018

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

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Mar 30, 2018

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. -

Sick sinus syndrome 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Mar 30, 2018

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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 04, 2023

This variant is present in population databases (rs199473338, gnomAD 0.001%). This sequence change replaces proline, which is neutral and non-polar, with arginine, which is basic and polar, at codon 2006 of the SCN5A protein (p.Pro2006Arg). This variant has not been reported in the literature in individuals affected with SCN5A-related conditions. ClinVar contains an entry for this variant (Variation ID: 68025). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be tolerated. 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. -

Progressive familial heart block, type 1A Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Mar 30, 2018

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. -

Long QT syndrome 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Mar 30, 2018

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. -

Cardiovascular phenotype Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 28, 2023

The p.P2006R variant (also known as c.6017C>G), located in coding exon 27 of the SCN5A gene, results from a C to G substitution at nucleotide position 6017. The proline at codon 2006 is replaced by arginine, an amino acid with dissimilar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Oct 02, 2023

This missense variant replaces proline with arginine at codon 2006 of the SCN5A protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with SCN5A-related 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. -

Congenital long QT syndrome Other:1

not provided, no classification provided

literature only

Cardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust

-

This variant has been reported as associated with Long QT syndrome in the following publications (PMID:10961955). This is a literature report, and does not necessarily reflect the clinical interpretation of the Imperial College / Royal Brompton Cardiovascular Genetics laboratory. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.083
CardioboostCm	Benign	0.0034
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.050
CADD	Benign	18
DANN	Benign	0.95
DEOGEN2	Benign	0.37	.;.;.;.;.;T;.;.;.
Eigen	Benign	-0.55
Eigen_PC	Benign	-0.46
FATHMM_MKL	Benign	0.51	D
LIST_S2	Uncertain	0.91	.;D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.42	D
MetaRNN	Benign	0.17	T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	-0.048	T
MutationAssessor	Benign	0.0	.;.;.;.;.;N;.;.;.
PrimateAI	Benign	0.26	T
PROVEAN	Benign	-0.31	N;N;N;N;N;N;N;N;N
REVEL	Uncertain	0.37
Sift	Benign	0.11	T;T;T;T;D;T;T;D;D
Sift4G	Benign	0.57	T;T;T;T;T;T;T;T;T
Polyphen		0.068	B;B;.;B;.;B;B;.;.
Vest4		0.16
MutPred		0.33		.;.;Loss of catalytic residue at P2005 (P = 0.0103);.;.;Loss of catalytic residue at P2005 (P = 0.0103);.;.;.;
MVP		0.68
MPC		0.72
ClinPred		0.091	T
GERP RS		4.6
Varity_R		0.031
gMVP		0.54

Splicing

Name	Calibrated prediction	Score	Prediction
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

Publications

LitVar

Other links and lift over

dbSNP: rs199473338; hg19: chr3-38591846;