rs727503411

Variant names:

• chr3-38633052-AG-A
• rs727503411
• NM_001099404.2:c.255delC

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.255delC​(p.Phe86SerfsTer11) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SCN5A NM_000335.5 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 0.156

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]

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 3-38633052-AG-A is Pathogenic according to our data. Variant chr3-38633052-AG-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 165160.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.255delC	p.Phe86SerfsTer11	frameshift_variant	Exon 2 of 28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.255delC	p.Phe86SerfsTer11	frameshift_variant	Exon 2 of 28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.255delC	p.Phe86SerfsTer11	frameshift_variant	Exon 2 of 28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.255delC	p.Phe86SerfsTer11	frameshift_variant	Exon 2 of 28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Mar 29, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ClinVar contains an entry for this variant (Variation ID: 165160). This sequence change creates a premature translational stop signal (p.Phe86Serfs*11) 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 variant has not been reported in the literature in individuals affected with SCN5A-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Brugada syndrome Pathogenic:1

Jan 31, 2014

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The Phe86fs variant in SCN5A has not been previously reported in individuals wit h cardiomyopathy or in large population studies. This variant is predicted to c ause a frameshift, which alters the protein's amino acid sequence beginning at c odon 86 and leads to a premature stop codon 11 codons downstream. This alterati on is then predicted to lead to a truncated or absent protein. Heterozygous loss of function variants in the SCN5A gene have been reported in individuals with B rugada syndrome (Kapplinger 2010), DCM (Olson 2005), ventricular fibrillation (C hen 1998), as well as AV block and cardiac conduction defects (Baruteau 2012) bu t it is not clear if all variants of this type cause disease. In summary, this variant is very likely pathogenic but additional evidence is needed to establish this with certainty. -

Computational scores

Source: dbNSFP v4.3

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: rs727503411; hg19: chr3-38674543;