chr3-38603926-G-A

Variant names:

• chr3-38603926-G-A
• rs199473575
• NM_001099404.2:c.1676C>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_198056.3(SCN5A):​c.1676C>T​(p.Thr559Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,878 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/24 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. T559K) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SCN5A NM_198056.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3 O:1
• Conservation: PhyloP100: 1.46
• Publications: 3 publications found

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 Gene-Disease associations (from GenCC):

• Brugada syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Brugada syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1E

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• familial long QT syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• long QT syndrome 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
• sick sinus syndrome 1

  Inheritance: AD, AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
• progressive familial heart block, type 1A

  Inheritance: SD, AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Genomics England PanelApp
• atrial standstill

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial atrial fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial sick sinus syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• paroxysmal familial ventricular fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• progressive familial heart block

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• catecholaminergic polymorphic ventricular tachycardia

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• short QT syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.17436394).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_198056.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN5A	NM_001099404.2	MANE Plus Clinical	c.1676C>T	p.Thr559Ile	missense	Exon 12 of 28	NP_001092874.1
	SCN5A	NM_000335.5	MANE Select	c.1676C>T	p.Thr559Ile	missense	Exon 12 of 28	NP_000326.2
	SCN5A	NM_198056.3		c.1676C>T	p.Thr559Ile	missense	Exon 12 of 28	NP_932173.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN5A	ENST00000413689.6	TSL:5 MANE Plus Clinical	c.1676C>T	p.Thr559Ile	missense	Exon 12 of 28	ENSP00000410257.1
	SCN5A	ENST00000423572.7	TSL:1 MANE Select	c.1676C>T	p.Thr559Ile	missense	Exon 12 of 28	ENSP00000398266.2
	SCN5A	ENST00000333535.9	TSL:1	c.1676C>T	p.Thr559Ile	missense	Exon 12 of 28	ENSP00000328968.4

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152220 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000161 AC: 4 AN: 249138 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000223

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461658 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727124

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26124

East Asian (EAS) AF: 0.0000504 AC: 2 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53374

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111870

Other (OTH) AF: 0.0000166 AC: 1 AN: 60372

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152220 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74368

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 41468

American (AMR) AF: 0.00 AC: 0 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10626

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68034

Other (OTH) AF: 0.00 AC: 0 AN: 2094

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.00000826 AC: 1

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	2	-	Cardiac arrhythmia (2)
-	1	-	not provided (2)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
CardioboostArm	Benign	0.0000015
CardioboostCm	Benign	0.0016
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.16
CADD	Benign	16
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.70	D
Eigen	Benign	-0.24
Eigen_PC	Benign	-0.22
FATHMM_MKL	Uncertain	0.86	D
LIST_S2	Benign	0.68	T
M_CAP	Pathogenic	0.41	D
MetaRNN	Benign	0.17	T
MetaSVM	Uncertain	-0.084	T
MutationAssessor	Benign	1.5	L
PhyloP100		1.5
PrimateAI	Benign	0.43	T
PROVEAN	Uncertain	-2.5	D
REVEL	Uncertain	0.30
Sift	Benign	0.038	D
Sift4G	Benign	0.098	T
Polyphen		0.26	B
Vest4		0.23
MutPred		0.39		Loss of catalytic residue at T559 (P = 0.0427)
MVP		0.53
MPC		0.41
ClinPred		0.12	T
GERP RS		2.4
Varity_R		0.062
gMVP		0.71
Mutation Taster		=31/69	disease causing

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

Other links and lift over

dbSNP: rs199473575; hg19: chr3-38645417; COSMIC: COSV100348218;