3-38550356-G-T

Variant names:

• chr3-38550356-G-T
• rs45489199
• NM_001099404.2:c.6016C>A

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.6013C>A​(p.Pro2005Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000261 in 1,534,686 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 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: 𝑓 0.0000067 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000022 (0 hom.)
• Consequence: SCN5A NM_000335.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.0910

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 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 the SCN5A gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 99 curated pathogenic missense variants (we use a threshold of 10). The gene has 60 curated benign missense variants. Gene score misZ: 2.7504 (below the threshold of 3.09). Trascript score misZ: 4.8279 (above the threshold of 3.09). GenCC associations: The gene is linked to 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=0.09178752).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.6016C>A	p.Pro2006Thr	missense_variant	Exon 28 of 28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.6013C>A	p.Pro2005Thr	missense_variant	Exon 28 of 28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.6016C>A	p.Pro2006Thr	missense_variant	Exon 28 of 28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.6013C>A	p.Pro2005Thr	missense_variant	Exon 28 of 28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes AF: 0.00000669 AC: 1 AN: 149550 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: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000149

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000217 AC: 3 AN: 1385136 Hom.: 0 Cov.: 31 AF XY: 0.00000147 AC XY: 1 AN XY: 678678

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: 0.00000280

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000669 AC: 1 AN: 149550 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 73064

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000149

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Uncertain:1

Jun 22, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The threonine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. This variant has not been reported in the literature in individuals affected with SCN5A-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.007%). This sequence change replaces proline, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 2006 of the SCN5A protein (p.Pro2006Thr). -

Cardiac arrhythmia Uncertain:1

Nov 15, 2021

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces proline with threonine 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 cardiovascular disorders in the literature. This variant has been identified in 1/31030 chromosomes 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	0.065
CardioboostCm	Benign	0.0033
BayesDel_addAF	Uncertain	0.053	T
BayesDel_noAF	Benign	-0.16
CADD	Benign	4.1
DANN	Benign	0.15
DEOGEN2	Benign	0.39	.;.;.;.;.;T;.;.;.
Eigen	Benign	-1.0
Eigen_PC	Benign	-0.99
FATHMM_MKL	Benign	0.072	N
LIST_S2	Benign	0.85	.;T;T;T;T;T;D;.;T
M_CAP	Pathogenic	0.37	D
MetaRNN	Benign	0.092	T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-0.33	T
MutationAssessor	Benign	-0.34	.;.;.;.;.;N;.;.;.
PrimateAI	Benign	0.24	T
PROVEAN	Benign	-0.74	N;N;N;N;N;N;N;N;N
REVEL	Uncertain	0.29
Sift	Benign	0.41	T;T;T;T;T;T;T;T;T
Sift4G	Benign	0.66	T;T;T;T;T;T;T;T;T
Polyphen		0.0	B;B;.;B;.;B;B;.;.
Vest4		0.088
MutPred		0.35		.;.;Loss of catalytic residue at P2005 (P = 0.0103);.;.;Loss of catalytic residue at P2005 (P = 0.0103);.;.;.;
MVP		0.62
MPC		0.57
ClinPred		0.067	T
GERP RS		-2.6
Varity_R		0.045
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: rs45489199; hg19: chr3-38591847;