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rs199472697

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000218.3(KCNQ1):c.521G>A(p.Arg174His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,612,404 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R174C) has been classified as Likely pathogenic.

Frequency

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

Consequence

KCNQ1
NM_000218.3 missense

Scores

16
1
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:7O:1

Conservation

PhyloP100: 9.42
Variant links:
Genes affected
KCNQ1 (HGNC:6294): (potassium voltage-gated channel subfamily Q member 1) This gene encodes a voltage-gated potassium channel required for repolarization phase of the cardiac action potential. This protein can form heteromultimers with two other potassium channel proteins, KCNE1 and KCNE3. Mutations in this gene are associated with hereditary long QT syndrome 1 (also known as Romano-Ward syndrome), Jervell and Lange-Nielsen syndrome, and familial atrial fibrillation. This gene exhibits tissue-specific imprinting, with preferential expression from the maternal allele in some tissues, and biallelic expression in others. This gene is located in a region of chromosome 11 amongst other imprinted genes that are associated with Beckwith-Wiedemann syndrome (BWS), and itself has been shown to be disrupted by chromosomal rearrangements in patients with BWS. Alternatively spliced transcript variants have been found for this gene. [provided by RefSeq, Aug 2011]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 9 uncertain in NM_000218.3
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr11-2570670-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 53058.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.991
PP5
Variant 11-2570671-G-A is Pathogenic according to our data. Variant chr11-2570671-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 53059.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr11-2570671-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
KCNQ1NM_000218.3 linkuse as main transcriptc.521G>A p.Arg174His missense_variant 3/16 ENST00000155840.12

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
KCNQ1ENST00000155840.12 linkuse as main transcriptc.521G>A p.Arg174His missense_variant 3/161 NM_000218.3 P1P51787-1
KCNQ1ENST00000335475.6 linkuse as main transcriptc.140G>A p.Arg47His missense_variant 3/161 P51787-2
KCNQ1ENST00000496887.7 linkuse as main transcriptc.260G>A p.Arg87His missense_variant 4/165
KCNQ1ENST00000646564.2 linkuse as main transcriptc.478-12764G>A intron_variant

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152192
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:
0.00
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
GnomAD3 exomes
AF:
0.00000401
AC:
1
AN:
249456
Hom.:
0
AF XY:
0.00000739
AC XY:
1
AN XY:
135338
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1460212
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
726504
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:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152192
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74356
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
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:7Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome 1 Pathogenic:2
Likely pathogenic, criteria provided, single submittercurationBiesecker Lab/Clinical Genomics Section, National Institutes of HealthNov 08, 2017- -
Pathogenic, criteria provided, single submitterclinical testingRoyal Brompton Clinical Genetics And Genomics Laboratory, NHS South East Genomic Laboratory HubSep 29, 2017This variant has been reported in multiple patients with LQTS (1. Denjoy et al. (1999) Arch Mal Coeur Vaiss. 92(5):557-63; Splawski et al. (2000) Circulation. 102(10):1178-85; Shimizu et al. (2004) J Am Coll Cardiol. 44(1):117-25; Moss et al. (2007) Circulation. 115(19):2481-9; Kapplinger et al. (2009) Heart Rhythm. 6(9):1297-303; Lupoglazoff et al J Am Coll Cardiol. 2004 Mar 3;43(5):82630; ClinVar variation ID 53059), and has been detected in a single individual in control populations (ExAC database 1/16484 alleles). Other variants at the same amino acid residue have also been reported in association with LQTS: p.Arg174Cys (pubmed: 9386136, 15840476, 19716085, 19934648, 9312006, 11668638); p.Arg174Leu (pubmed: 21956039); p.Arg174Pro (pubmed: 16414944). This variant occurs in the Transmembrane/Linker/Pore region of KCNQ1. Variants found in this region have been shown to have a high probability of pathogenicity (Kapa et al. Circulation. 2009 Nov 3; 120(18): 1752–1760). In silico analysis predicts pathogenicity (SIFT; PolyPhen; Mutation Taster; LRT, FATHMM; MutationAssessor) but these predictions have not been confirmed by published functional studies. The affected amino acid residue is highly conserved across species. -
not provided Pathogenic:2
Likely pathogenic, no assertion criteria providedclinical testingStanford Center for Inherited Cardiovascular Disease, Stanford UniversityFeb 08, 2012Note this variant was found in clinical genetic testing performed by one or more labs who may also submit to ClinVar. Thus any internal case data may overlap with the internal case data of other labs. The interpretation reviewed below is that of the Stanford Center for Inherited Cardiovascular Disease. KCNQ1 p.Arg174His Based on the information reviewed below, we classify it as likely disease causing. This variant has previously been reported multiple times, in ~7 unrelated individuals with LQTS (it is unclear if there is any overlap in individuals reported in the following papers). Splawski et al. (2000) reported it for the first time in a proband with LQTS. Shimizu et al. (2004) described its effects in 1 Japanese family. Lupoglazoff et al. (2004) reported it in a neonate with sinus bradycardia and prolonged QT of 500 msec. Moss et al. (2007) reported it in 2 unrelated families in the U.S. International/Netherlands/Japanese LQTS Registries. Kapplinger et al. (2009) reported it in one individual tested for LQTS at Familion. In 2009, clinicians from Kaiser San Diego and UCSD reported it in an abstract at ASHG as a homozygous mutation in a neonate with Jervell and Lange-Nielsen syndrome, whose family members (maternal and paternal) had LQTS. There is no known published segregation data. We do have segregation data within a family at our center, however, and the variant tracks with disease. Other variants at this same amino acid residue have also been reported in association with LQTS according to HGMD: p.Arg174Cys, p.Arg174Leu, p.Arg174Pro. This is a conservative amino acid change, resulting in the replacement of a positively charged arginine with a positively charged histidine, but the side chains are very different in shape. According to cardiodb.org, Arg174 is entirely conserved across 32 paralogue channel proteins. Variation at nearby residues (+10 amino acids) has been associated with LQTS, which supports the functional importance of this region of the protein: p.Gly168Arg, p.Thr169Arg, Glu170Gly, p.Val172Met, p.Val173Asp, p.Ala178Pro, p.Ala178Thr, p.Gly179Ser, p.Lys183Arg, p.Lys183Met, p.Tyr184His, p.Tyr184Ser (HGMD professional version as of January 17, 2014). Arg174 is in a transmembrane spanning region of KCNQ1, and such variants have been shown to have a higher likelihood of being deleterious than variants in other regions of the protein (Kapa et al. 2009). In silico analysis with PolyPhen-2 (http://genetics.bwh.harvard.edu/pph2/) predicts the variant to be “Probably Damaging” with a score of 1.0 In total the variant has not been seen in over 7500 published controls and individuals from publicly available population datasets. Kapplinger et al. (2009) did not observe it in 1300 ethnically diverse controls: 47% Caucasian, 26% African-American, 11% Hispanic, 10% Asian, 6% unknown/other. Splawski et al. (200) did not find it in 200 controls. There is no variation at this residue listed in the NHLBI Exome Sequencing Project dataset (http://evs.gs.washington.edu/EVS/), which currently includes variant calls on ~4300 Caucasian and ~2200 African American individuals. The phenotype of the ESP individuals is not publicly available, however the cohorts that were merged to create this dataset were all either general population samples or samples recruited for common cardiovascular disease such as hypertension. There is also no variation at this residue listed in 1000 Genomes (http://browser.1000genomes.org/index.htm) as of November 6, 2014. -
Likely pathogenic, criteria provided, single submitterclinical testingMolecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart InstituteJul 31, 2019- -
Beckwith-Wiedemann syndrome;C1837014:Atrial fibrillation, familial, 3;C1865019:Short QT syndrome type 2;C4551509:Jervell and Lange-Nielsen syndrome 1;C4551647:Long QT syndrome 1 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsDec 03, 2021- -
Long QT syndrome Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingInvitaeDec 18, 2023This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 174 of the KCNQ1 protein (p.Arg174His). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individuals with long QT syndrome (PMID: 10973849, 14998624, 19716085, 23130128; Invitae). ClinVar contains an entry for this variant (Variation ID: 53059). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt KCNQ1 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects KCNQ1 function (PMID: 29532034, 30571187). This variant disrupts the p.Arg174 amino acid residue in KCNQ1. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 9386136, 15840476, 23130128, 23392653). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -
Cardiovascular phenotype Pathogenic:1
Likely pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsNov 16, 2023The p.R174H variant (also known as c.521G>A), located in coding exon 3 of the KCNQ1 gene, results from a G to A substitution at nucleotide position 521. The arginine at codon 174 is replaced by histidine, an amino acid with highly similar properties. This variant has been described in association with long QT syndrome (LQTS) (Splawski I et al. Circulation. 2000;102(10):1178-85; Lupoglazoff JM et al. J. Am. Coll. Cardiol. 2004;43(5):826-30; Shimizu W et al. J. Am. Coll. Cardiol. 2004;44(1):117-25; Kapplinger JD et al. Heart Rhythm. 2009;6(9):1297-303). Functional analysis suggests this alteration causes a dominant negative trafficking defect (Vanoye CG et al. Circ Genom Precis Med, 2018 11;11:e002345; Huang H et al. Sci Adv. 2018;4:eaar2631). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the majority of available evidence to date, this variant is likely to be pathogenic. -
Congenital long QT syndrome Other:1
not provided, no classification providedliterature onlyCardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust-This variant has been reported as associated with Long QT syndrome in the following publications (PMID:10367071;PMID:10973849;PMID:14998624;PMID:19716085;PMID:15234419;PMID:17470695). 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
0.99
CardioboostArm
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.58
D
BayesDel_noAF
Pathogenic
0.60
Cadd
Pathogenic
33
Dann
Pathogenic
1.0
Eigen
Pathogenic
0.82
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Pathogenic
1.0
D;D;D
M_CAP
Pathogenic
0.87
D
MetaRNN
Pathogenic
0.99
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationTaster
Benign
1.0
D;D
PrimateAI
Pathogenic
0.79
T
PROVEAN
Pathogenic
-4.7
D;D;D
REVEL
Pathogenic
0.97
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0010
D;D;D
Polyphen
1.0
.;D;.
Vest4
0.98, 0.95
MutPred
0.96
.;Loss of MoRF binding (P = 0.0099);.;
MVP
0.99
MPC
1.3
ClinPred
1.0
D
GERP RS
4.4
Varity_R
0.94
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: rs199472697; hg19: chr11-2591901; API