rs199473105

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP2PP3_Strong

The NM_000335.5(SCN5A):​c.1190T>C​(p.Ile397Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,864 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: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

SCN5A
NM_000335.5 missense

Scores

16
3
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4O:1

Conservation

PhyloP100: 9.32
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

PM1
In a transmembrane_region Helical; Name=S6 of repeat I (size 20) in uniprot entity SCN5A_HUMAN there are 6 pathogenic changes around while only 1 benign (86%) 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, 0.981

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SCN5ANM_001099404.2 linkc.1190T>C p.Ile397Thr missense_variant Exon 10 of 28 ENST00000413689.6 NP_001092874.1 Q14524H9KVD2
SCN5ANM_000335.5 linkc.1190T>C p.Ile397Thr missense_variant Exon 10 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.1190T>C p.Ile397Thr missense_variant Exon 10 of 28 5 NM_001099404.2 ENSP00000410257.1 H9KVD2
SCN5AENST00000423572.7 linkc.1190T>C p.Ile397Thr missense_variant Exon 10 of 28 1 NM_000335.5 ENSP00000398266.2 Q14524-2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152206
Hom.:
0
Cov.:
32
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:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
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:
727120
show subpopulations
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:
0.00000270
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152206
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74368
show subpopulations
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:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Dec 01, 2023
GeneDx
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Observed in an individual referred for LQTS genetic testing (PMID: 19716085); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 34803699, 19716085, 36136372) -

Jan 06, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 397 of the SCN5A protein (p.Ile397Thr). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with referral for long QT syndrome testing (PMID: 19716085). ClinVar contains an entry for this variant (Variation ID: 67644). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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. -

not specified Uncertain:1
Sep 26, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: SCN5A c.1190T>C (p.Ile397Thr) results in a non-conservative amino acid change located in the Ion transport domain (IPR005821) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 249224 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1190T>C has been reported in the literature in settings of multigene panel testing in at-least one individual referred for long QT syndrome (LQTS) (example, Kapplinger_2009). These report(s) do not provide unequivocal conclusions about association of the variant with Arrhythmia/LQTS. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Two clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. One laboratory classified the variant as likely pathogenic, and one laboratory classified the variant as uncertain significance citing overlapping evidence utilized in the context of this evaluation. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Cardiac arrhythmia Uncertain:1
Aug 06, 2024
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 isoleucine with threonine at codon 397 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). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in one individual affected with long QT syndrome (PMID: 19716085). 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. -

Congenital long QT 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 Long QT syndrome in the following publications (PMID:19716085). 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
Pathogenic
0.96
CardioboostCm
Uncertain
0.90
BayesDel_addAF
Pathogenic
0.57
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.97
.;.;.;.;.;D;.;.;.
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.93
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
.;D;D;D;D;D;D;.;D
M_CAP
Pathogenic
0.85
D
MetaRNN
Pathogenic
0.98
D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.2
.;M;.;.;.;M;.;.;.
PrimateAI
Pathogenic
0.90
D
PROVEAN
Pathogenic
-4.9
D;D;D;D;D;D;D;D;D
REVEL
Pathogenic
0.99
Sift
Pathogenic
0.0
D;D;D;D;D;D;D;D;D
Sift4G
Uncertain
0.019
D;D;D;D;D;D;D;D;D
Polyphen
1.0
D;D;.;D;.;D;D;.;.
Vest4
0.94
MutPred
0.87
Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);Loss of stability (P = 0.0162);
MVP
0.99
MPC
1.3
ClinPred
1.0
D
GERP RS
5.5
Varity_R
0.88
gMVP
0.99

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs199473105; hg19: chr3-38647590; API