NM_001099404.2:c.3911C>T
Variant summary
Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1PP3_Strong
The NM_001099404.2(SCN5A):c.3911C>T(p.Thr1304Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000343 in 1,613,484 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 15/24 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. T1304T) has been classified as Likely benign.
Frequency
Consequence
NM_001099404.2 missense
Scores
Clinical Significance
Conservation
Publications
- Brugada syndromeInheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
- Brugada syndrome 1Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Laboratory for Molecular Medicine, G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
- dilated cardiomyopathyInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- dilated cardiomyopathy 1EInheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
- familial long QT syndromeInheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
- long QT syndrome 3Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
- sick sinus syndrome 1Inheritance: AD, AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
- progressive familial heart block, type 1AInheritance: SD, AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Genomics England PanelApp
- atrial standstillInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- familial atrial fibrillationInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- familial isolated dilated cardiomyopathyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- familial sick sinus syndromeInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- paroxysmal familial ventricular fibrillationInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- progressive familial heart blockInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- arrhythmogenic right ventricular cardiomyopathyInheritance: AD Classification: LIMITED Submitted by: ClinGen
- catecholaminergic polymorphic ventricular tachycardiaInheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
- short QT syndromeInheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
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ACMG classification
Our verdict: Likely_pathogenic. The variant received 6 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| SCN5A | NM_001099404.2 | c.3911C>T | p.Thr1304Met | missense_variant | Exon 22 of 28 | ENST00000413689.6 | NP_001092874.1 | |
| SCN5A | NM_000335.5 | c.3908C>T | p.Thr1303Met | missense_variant | Exon 22 of 28 | ENST00000423572.7 | NP_000326.2 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| SCN5A | ENST00000413689.6 | c.3911C>T | p.Thr1304Met | missense_variant | Exon 22 of 28 | 5 | NM_001099404.2 | ENSP00000410257.1 | ||
| SCN5A | ENST00000423572.7 | c.3908C>T | p.Thr1303Met | missense_variant | Exon 22 of 28 | 1 | NM_000335.5 | ENSP00000398266.2 |
Frequencies
GnomAD3 genomes AF: 0.000217 AC: 33AN: 152220Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.000178 AC: 44AN: 247644 AF XY: 0.000208 show subpopulations
GnomAD4 exome AF: 0.000357 AC: 521AN: 1461146Hom.: 0 Cov.: 31 AF XY: 0.000341 AC XY: 248AN XY: 726770 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.000217 AC: 33AN: 152338Hom.: 0 Cov.: 33 AF XY: 0.000161 AC XY: 12AN XY: 74480 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
not provided Uncertain:6
This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 1304 of the SCN5A protein (p.Thr1304Met). This variant is present in population databases (rs199473603, gnomAD 0.03%). This missense change has been observed in individual(s) with SCN5A-related conditions (PMID: 10508990, 17210839, 17210841, 19716085, 19841300, 24631775, 25210526, 28341588, 30847666). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 67835). 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. Experimental studies have shown that this missense change affects SCN5A function (PMID: 17210841). 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. -
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Reported in individuals with various cardiac phenotypes, including LQTS, Brugada syndrome, lone atrial fibrillation, sudden infant death syndrome, cardiomyopathy, and T-wave inversion (PMID: 17210839, 10508990, 10973849, 19716085, 22685113, 25210526, 23465283, 29764897, 31514951, 34065239); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Functional studies have been reported and show conflicting results (PMID: 17210841, 24613995); This variant is associated with the following publications: (PMID: 10973849, 19716085, 28316956, 31514951, 30193851, 22685113, 23465283, 22378279, 25637381, 25210526, 10961955, 18503232, 23272275, 24055113, 24613995, 25351510, 25410959, 25904541, 25898860, 27153395, 29247119, 28412158, 28341588, 30677491, 28988457, 31019283, 31043699, 32048431, 30291343, 30847666, 29764897, 26743238, 19841300, 24144883, 24631775, 26746457, 31395126, 34426522, 34065239, 34621001, 34461752, 33772059, 35060774, 30203441, 10508990, 17210839, 29790872, 17210841, 37937776, 36396199, 35534676, 36129056, 37965733) -
SCN5A: PP3 -
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The SCN5A c.3911C>T; p.Thr1304Met variant (rs199473603) is reported in the literature in individuals affected with long QT syndrome (Kapa 2009, Wattanasirichaigoon 1999) or Brugada syndrome (Kim 2014), which have different mechanisms of pathogenicity. This variant is also reported with conflicting interpretations by multiple laboratories in ClinVar (Variation ID: 67835), and is found in the non-Finnish European population with an allele frequency of 0.031% (40/127748 alleles) in the Genome Aggregation Database. The threonine at codon 1304 is highly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is deleterious. However, functional analyses of the variant protein show conflicting effects on channel function (Beyder 2014, Wang 2007). Due to conflicting information, the clinical significance of the p.Thr1304Met variant is uncertain at this time. References: Beyder A et al. Loss-of-function of the voltage-gated sodium channel NaV1.5 (channelopathies) in patients with irritable bowel syndrome. Gastroenterology. 2014 Jun;146(7):1659-1668. Kapa S et al. Genetic testing for long-QT syndrome: distinguishing pathogenic mutations from benign variants. Circulation. 2009 Nov 3;120(18):1752-60. Kim G et al. A pediatric case of Brugada syndrome diagnosed by fever-provoked ventricular tachycardia. Korean J Pediatr. 2014 Aug;57(8):374-8. Wang DW et al. Cardiac sodium channel dysfunction in sudden infant death syndrome. Circulation. 2007 Jan 23;115(3):368-76. Wattanasirichaigoon D et al. Sodium channel abnormalities are infrequent in patients with long QT syndrome: identification of two novel SCN5A mutations. Am J Med Genet. 1999 Oct 29;86(5):470-6. -
Brugada syndrome 1 Uncertain:4
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The SCN5A c.3911C>T variant (rs199473603) is present in population databases (gnomAD 0.03%). Computational prediction analyses (Polyphen-2, SIFT) suggest that this variant has deleterious effect on protein structure and function. Functional studies have shown conflicting results in channel function (PMID: 17210841, 24613995). This variant was reported in individuals with long QT syndrome (PMID: 17210839, 19716085, 19841300); Brugada syndrome (PMID: 34461752, 25210526), sudden unexplained death (PMID: 17210839, 17210841, 24631775, 32652122). Based on conflicting evidence, the clinical role of SCN5A c.3911C>T variant cannot be determined. Therefore, it has been classified as a Variant of Uncertain Significance. -
This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -
Long QT syndrome 3 Pathogenic:2Uncertain:1
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This variant has been previously reported as disease-causing. It was an incidental finding in our study, maternally inherited in a 8-year-old male with medulloblastoma. -
not specified Uncertain:2
Variant summary: SCN5A c.3911C>T (p.Thr1304Met) 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 allele was found at a frequency of 0.00018 in 247644 control chromosomes. The observed variant frequency is approximately 8.53 fold of the estimated maximal expected allele frequency for a pathogenic variant in SCN5A causing Long QT Syndrome phenotype (2.1e-05). c.3911C>T has been reported in the literature in individuals affected with Long QT Syndrome and other related conditions (e.g. Wattanasirichaigoon_1999, Arnestad_2007, Kapplinger_2009, Kapa_2009, van Lint_2019). These data indicate that the variant is likely to be associated with disease. At least one publication reports experimental evidence evaluating an impact on protein function and demonstrates an affect on protein function (Wang_2007). The following publications have been ascertained in the context of this evaluation (PMID: 17210839, 37937776, 35534676, 19841300, 19716085, 36396199, 17210841, 10508990, 39486665, 36129056, 30847666). ClinVar contains an entry for this variant (Variation ID: 67835). Based on the evidence outlined above, the variant was classified as uncertain significance. -
The p.Thr1304Met variant in SCN5A has been reported in 3 individuals with long Q T syndrome, 1 infant with sudden infant death syndrome, 1 individual with Brugad a syndrome, 1 individual with early-onset atrial fibrillation (Wattanasirichaigo on 1999, Priori 2000, Splawski 2000, Arnestad 2007, Olesen 2012, Kim 2014). This variant segregated with LQTS in 2 affected relatives from 1 family and with Br ugada syndrome in 1 affected relative from 1 family. However, other clinical lab oratories have observed this variant in individuals who carried other disease-ca using variants (GeneDx, Emory, Invitae; personal communication) and this variant has been reported in multiple healthy individuals (Weeke 2015, Kapplinger 2015) . Additionally, it is unclear if the same variant would be causative for such a diverse set of phenotypes, suggesting that it may not have a functional effect. This variant has also been identified in 0.03% (35/126116) of European chromosom es by the Genome Aggregation Database (gnomAD, http://gnomad.broadinstitute.org; dbSNP rs199473603). Additionally, in vitro functional studies have shown confli cting results (Want 2007, Makita 2008, Beyder 2014). In summary, due to the pres ence of conflicting data, the clinical significance of the p.Thr1304Met variant is uncertain. ACMG/AMP Criteria applied: PP1; BP5. -
Brugada syndrome Pathogenic:1
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Long QT syndrome Pathogenic:1
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SCN5A-related disorder Uncertain:1
The SCN5A c.3911C>T variant is predicted to result in the amino acid substitution p.Thr1304Met. This variant was reported in individuals with long QT syndrome and Brugada syndrome (Wattanasirichaigoon et al. 1999. PMID: 10508990; Arnestad et al. 2007. PMID: 17210839; Kapplinger et al. 2009. PMID: 19716085; Kapa et al. 2009. PMID: 19841300; Table SVI, Milman et al. 2021. PubMed ID: 34461752). Functional studies showed conflicting evidences of pathogenicity for this variant. Although one study suggested this variant significantly increased persistent sodium currents and faster recovery from inactivation (Wang et al. 2007. PMID: 17210841), another demonstrated no difference from wild type SCN5A (Beyder et al. 2014. PubMed ID: 24613995). This variant also had conflicting interpretations of pathogenicity in the literature ranging from benign to pathogenic (Table S1, Amendola et al. 2015. PMID: 25637381; Table S1, Paludan-Müller et al. 2019. PubMed ID: 31043699; Table SVI, Milman et al. 2021. PubMed ID: 34461752). This variant is reported in 0.031% of alleles in individuals of European (Non-Finnish) descent in gnomAD and has conflicting interpretations of benign, uncertain significance, likely pathogenic, and pathogenic in ClinVar (www.ncbi.nlm.nih.gov/clinvar/variation/67835/). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
Conduction disorder of the heart Uncertain:1
This variant is classified as a Variant of Uncertain Significance based on the following ACMG/AMP criteria: BS2, PP3, and PS3. Published functional in vitro and in vivio evidence (Wang et al 2007, Anderson et al 2017) supports this variant having an effect on the SCN5A protein, but population frequency (MAF of 0.0003 in non-finnish Europeans) is high compared to frequency of disease. -
Cardiovascular phenotype Uncertain:1
The p.T1304M variant (also known as c.3911C>T), located in coding exon 21 of the SCN5A gene, results from a C to T substitution at nucleotide position 3911. The threonine at codon 1304 is replaced by methionine, an amino acid with similar properties, and is located in the transmembrane DIII-S4 region. This alteration has been reported in association with long QT syndrome (Wattanasirichaigoon D et al. Am. J. Med. Genet., 1999 Oct;86:470-6; Kapplinger JD et al. Heart Rhythm, 2009 Sep;6:1297-303). In one family, alteration carriers showed variable clinical and electrophysiological phenotypes with several having borderline findings (Wattanasirichaigoon D et al. Am. J. Med. Genet., 1999 Oct;86:470-6). This alteration was also detected in individuals with a transient Brugada pattern, lone atrial fibrillation, or sudden infant death syndrome (Wang DW et al. Circulation, 2007 Jan;115:368-76; Olesen MS et al. Circ Cardiovasc Genet, 2012 Aug;5:450-9; Wang D et al. Forensic Sci. Int., 2014 Apr;237:90-9; Kim G et al. Korean J Pediatr, 2014 Aug;57:374-8). In addition, this alteration was reported in hypertrophic cardiomyopathy, dilated cardiomyopathy cohorts as well as exome sequencing and cohorts not selected for the presence of cardiovascular disease; however, limited clinical information was provided (Andreasen C et al. Can J Cardio. 2013;29(9):1104-9; Dorschner MO et al. Am J Hum Genet. 2013;93(4):631-40; Lopes LR et al. Heart, 2015 Feb;101:294-301; Amendola LM et al. Genome Res., 2015 Mar;25:305-15; Van Driest SL et al. JAMA, 2016 Jan;315:47-57; Gigli M et al. J Am Coll Cardiol. 2019 09;74(11):1480-1490; Diebold I et al. Hum Mutat. 2020 05;41(5):1025-1032). While some research groups reported that this alteration would lead to gain of function effects (Wang DW et al. Circulation, 2007 Jan;115:368-76; Arnestad M et al. Circulation, 2007 Jan;115:361-7), others found no significant difference between mutant and wild type channel function (Beyder A et al. Gastroenterology, 2014 Jun;146:1659-1668; Makita N et al. J. Clin. Invest., 2008 Jun;118:2219-29); however, the experimental systems were not the same and the physiological significance of these results is unclear. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is conflicting at this time, the clinical significance of this alteration remains unclear. -
Cardiac arrhythmia Benign:1
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Congenital long QT syndrome Other:1
This variant has been reported as associated with Long QT syndrome in the following publications (PMID:10508990;PMID:10961955;PMID:17210839;PMID:19716085;PMID:19841300;PMID:17210841;PMID:22378279;PMID:22685113). 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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at