rs1474459822

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM2PM4_SupportingPP3PP5

The NM_001099404.2(SCN5A):​c.5623_5625dupATG​(p.Met1875dup) variant causes a conservative inframe insertion change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,872 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

SCN5A
NM_001099404.2 conservative_inframe_insertion

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:4U:2

Conservation

PhyloP100: 7.90

Publications

1 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM4
Nonframeshift variant in NON repetitive region in NM_001099404.2. Strenght limited to Supporting due to length of the change: 1aa.
PP3
No computational evidence supports a deleterious effect, but strongly conserved according to phyloP
PP5
Variant 3-38550746-C-CCAT is Pathogenic according to our data. Variant chr3-38550746-C-CCAT is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 520459.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN5ANM_001099404.2 linkc.5623_5625dupATG p.Met1875dup conservative_inframe_insertion Exon 28 of 28 ENST00000413689.6 NP_001092874.1 Q14524H9KVD2
SCN5ANM_000335.5 linkc.5620_5622dupATG p.Met1874dup conservative_inframe_insertion Exon 28 of 28 ENST00000423572.7 NP_000326.2 Q14524-2Q86V90

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SCN5AENST00000413689.6 linkc.5623_5625dupATG p.Met1875dup conservative_inframe_insertion Exon 28 of 28 5 NM_001099404.2 ENSP00000410257.1 H9KVD2
SCN5AENST00000423572.7 linkc.5620_5622dupATG p.Met1874dup conservative_inframe_insertion Exon 28 of 28 1 NM_000335.5 ENSP00000398266.2 Q14524-2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152160
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000194
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:
0.00000401
AC:
1
AN:
249278
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000556
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461712
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
727138
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53402
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111870
Other (OTH)
AF:
0.00
AC:
0
AN:
60374
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152160
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74320
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.000194
AC:
1
AN:
5162
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:4Uncertain:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Brugada syndrome 1 Pathogenic:2
May 21, 2020
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.1.1, this variant is classified as likely pathogenic. Following criteria are met: 0103 - Both loss- and gain-of-function are known mechanisms of disease for this gene. PTCs cause a loss of function mechanism, while missense are both loss and gain of function (OMIM, PMID: 29806494). (N) 0108 - This gene is known to be associated with both recessive and dominant disease. Recessive disease is caused by loss of function variants, while dominant disease is both loss and gain of function (OMIM, PMID: 29806494). (N) 0213 - In-frame insertion/deletion in a non-repetitive region that has high conservation (exon 28). (P) 0251 - Variant is heterozygous. (N) 0302 - Variant is present in gnomAD <0.001 for a dominant condition (2 heterozygotes, 0 homozygotes). (P) 0507 - Identified variant type is not compatible with in silico predictions of pathogenicity. (N) 0600 - Variant is located in an annotated domain or motif, (5th helice of the carboxyl-terminal region; PMID: 19272188). (N) 0705 - No comparable variants have previous evidence for pathogenicity. A missense variant are this same residue (p.Met1875Thr) has been commonly reported as a pathogenic variant causing atrial fibrillation (ClinVar). (N) 0803 - Low previous evidence of pathogenicity in two unrelated individuals, one with Brugada syndrome (ClinVar, PMID: 19272188). (P) 0905 - No segregation evidence has been identified for this variant. (N) 1002 - Moderate functional evidence supporting abnormal protein function. Transfected cells displayed mostly loss of function effects on steady state channel activation and inactivation and recovery (PMID: 19272188). (P) 1208 - Inheritance information for this variant is not currently available. (N) Legend: (P) - Pathogenic, (N) - Neutral, (B) - Benign -

Mar 10, 2021
Genetics and Molecular Pathology, SA Pathology
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

SUDDEN INFANT DEATH SYNDROME;C1832680:Dilated cardiomyopathy 1E;C1837845:Sick sinus syndrome 1;C1859062:Long QT syndrome 3;C1879286:Progressive familial heart block, type 1A;C2751898:Ventricular fibrillation, paroxysmal familial, type 1;C3151464:Atrial fibrillation, familial, 10;C4551804:Brugada syndrome 1 Pathogenic:1
-
Juno Genomics, Hangzhou Juno Genomics, Inc
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

PM2_Supporting+PM4+PS3_Supporting+PS4_Supporting+PP4 -

not provided Pathogenic:1
Nov 21, 2016
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Uncertain:1
Aug 26, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.5623_5625dupATG variant (also known as p.M1875dup), located in coding exon 27 of the SCN5A gene, results from an in-frame duplication of ATG at nucleotide positions 5623 to 5625. This results in the duplication of an extra methionine residue between codons 1875 and 1876. This variant has been previously detected in an individual reported to have Brugada syndrome (Hsueh CH et al. J Biomed Sci, 2009 Feb;16:23). In vitro studies by one group suggest this variant may have some impact on protein function (Hsueh CH et al. J Biomed Sci, 2009 Feb;16:23). This amino acid region is highly conserved in available vertebrate species and the impacted region is critical for protein function (Ambry internal data). In addition, this alteration is predicted to be deleterious by in silico analysis (Choi Y et al. PLoS ONE. 2012; 7(10):e46688). Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia Uncertain:1
Aug 28, 2023
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant causes a duplication of methionine at codon 1875 of the SCN5A protein. This variant is also known as p.Met1874dup based on a different transcript NM_000335.5. This variant is found within the highly conserved C-terminal region (a.a. 1773-2016). Rare nontruncating variants in this region have been shown to be significantly overrepresented in individuals with Brugada syndrome (PMID: 32893267). A functional study has shown that this variant traffics to the cell surface similarly to wildtype channels, but has altered electrophysiological properties (PMID: 19272188). This variant has been reported in an individual affected with Brugada syndrome (PMID: 19272188). This variant has been identified in 2/280672 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
PhyloP100
7.9
Mutation Taster
=5/95
disease causing (ClinVar)

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs1474459822; hg19: chr3-38592237; API