chr3-38566567-A-G

Variant names:

• chr3-38566567-A-G
• rs199473205
• NM_001099404.2:c.3682T>C

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_000335.5(SCN5A):​c.3679T>C​(p.Tyr1227His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000753 in 1,461,492 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: SCN5A NM_000335.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2 O:1
• Conservation: PhyloP100: 7.36

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a topological_domain Extracellular (size 12) in uniprot entity SCN5A_HUMAN there are 9 pathogenic changes around while only 1 benign (90%) in NM_000335.5
• PM2: Very rare variant in population databases, with high coverage
• 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.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.939

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SCN5A	NM_001099404.2	c.3682T>C	p.Tyr1228His	missense_variant	Exon 21 of 28	ENST00000413689.6	NP_001092874.1
SCN5A	NM_000335.5	c.3679T>C	p.Tyr1227His	missense_variant	Exon 21 of 28	ENST00000423572.7	NP_000326.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SCN5A	ENST00000413689.6	c.3682T>C	p.Tyr1228His	missense_variant	Exon 21 of 28	5	NM_001099404.2	ENSP00000410257.1
SCN5A	ENST00000423572.7	c.3679T>C	p.Tyr1227His	missense_variant	Exon 21 of 28	1	NM_000335.5	ENSP00000398266.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000401 AC: 1 AN: 249662 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135384

Gnomad AFR exome AF: 0.0000643

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000753 AC: 11 AN: 1461492 Hom.: 0 Cov.: 31 AF XY: 0.00000413 AC XY: 3 AN XY: 727028

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: 0.00000989

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Cardiovascular phenotype Uncertain:1

Jul 08, 2019

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.3682T>C (p.Y1228H) alteration is located in exon 21 (coding exon 20) of the SCN5A gene. This alteration results from a T to C substitution at nucleotide position 3682, causing the tyrosine (Y) at amino acid position 1228 to be replaced by a histidine (H). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia Uncertain:1

Aug 23, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces tyrosine with histidine at codon 1228 of the SCN5A protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 0.7, PMID: 27666373). A functional study has shown that this variant has no significant impact on channel current (PMID: 34930020). This variant has been reported in an individual suspected of having Brugada syndrome and in an individual affected with syncope (PMID: 16643399, 20129283, 34930020). This variant has been identified in 1/249662 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. -

Brugada syndrome Other:1

-

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

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

This variant has been reported as associated with Brugada syndrome in the following publications (PMID:20129283). 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	0.12
CardioboostCm	Uncertain	0.14
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.46
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	.;.;.;.;.;D;.;.;.
Eigen	Benign	0.14
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.91	.;D;D;D;D;D;D;.;D
M_CAP	Pathogenic	0.31	D
MetaRNN	Pathogenic	0.94	D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.79	D
MutationAssessor	Benign	1.3	.;.;.;.;.;L;.;.;.
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-4.5	D;D;D;D;D;D;D;D;D
REVEL	Pathogenic	0.85
Sift	Benign	0.051	T;D;T;T;T;T;D;T;T
Sift4G	Benign	0.34	T;T;T;T;T;T;T;T;T
Polyphen		0.047	B;B;.;B;.;P;D;.;.
Vest4		0.92
MutPred		0.89		Loss of sheet (P = 0.0228);.;Loss of sheet (P = 0.0228);Loss of sheet (P = 0.0228);.;Loss of sheet (P = 0.0228);.;.;.;
MVP		0.95
MPC		1.6
ClinPred		0.81	D
GERP RS		4.5
Varity_R		0.44
gMVP		0.92

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: rs199473205; hg19: chr3-38608058;