3-38633208-G-C

Position:

• chr3-38633208-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The ENST00000423572.7(SCN5A):​c.100C>G​(p.Arg34Gly) variant causes a missense 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R34C) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SCN5A ENST00000423572.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.63

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 Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a topological_domain Cytoplasmic (size 130) in uniprot entity SCN5A_HUMAN there are 24 pathogenic changes around while only 9 benign (73%) in ENST00000423572.7
• PM2: Very rare variant in population databases, with high coverage
• 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.100C>G	p.Arg34Gly	missense_variant	2/28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.100C>G	p.Arg34Gly	missense_variant	2/28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.100C>G	p.Arg34Gly	missense_variant	2/28	5	NM_001099404.2	ENSP00000410257	P4
SCN5A	ENST00000423572.7	c.100C>G	p.Arg34Gly	missense_variant	2/28	1	NM_000335.5	ENSP00000398266	A1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cardiac arrhythmia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Mar 01, 2022

This missense variant replaces arginine with glycine at codon 34 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 cardiovascular 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.082
CardioboostCm	Benign	0.0012
BayesDel_addAF	Uncertain	0.097	D
BayesDel_noAF	Benign	-0.10
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.72	.;.;.;.;.;D;.;.;.;T;T
Eigen	Benign	0.096
Eigen_PC	Benign	0.11
FATHMM_MKL	Uncertain	0.82	D
LIST_S2	Uncertain	0.92	.;D;D;D;D;D;D;.;D;D;D
M_CAP	Pathogenic	0.49	D
MetaRNN	Uncertain	0.53	D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.36	D
MutationAssessor	Uncertain	2.2	.;M;.;.;.;M;.;.;.;.;.
MutationTaster	Benign	0.77	D;D;D;D;D;D;D;D;D;D
PrimateAI	Benign	0.35	T
PROVEAN	Uncertain	-3.1	D;D;D;D;D;D;D;D;D;.;D
REVEL	Uncertain	0.45
Sift	Uncertain	0.0020	D;D;D;D;D;D;D;D;D;.;D
Sift4G	Uncertain	0.0040	D;D;D;D;D;D;D;D;D;D;.
Polyphen		0.65	P;B;.;P;.;B;B;.;.;.;.
Vest4		0.55
MutPred		0.32		Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);Loss of MoRF binding (P = 0.0026);
MVP		0.76
MPC		0.78
ClinPred		0.96	D
GERP RS		4.5
Varity_R		0.19
gMVP		0.47

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: rs6791924; hg19: chr3-38674699;