rs199473395

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM5PP3_Strong

The NM_000218.3(KCNQ1):​c.541C>T​(p.Arg181Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000192 in 1,612,594 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R181H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000020 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

10
6
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5O:1

Conservation

PhyloP100: 2.82
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 Likely_pathogenic. Variant got 8 ACMG points.

PM1
In a hotspot region, there are 10 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_000218.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chr11-2570692-G-A is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.949

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
KCNQ1NM_000218.3 linkuse as main transcriptc.541C>T p.Arg181Cys missense_variant 3/16 ENST00000155840.12

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
KCNQ1ENST00000155840.12 linkuse as main transcriptc.541C>T p.Arg181Cys missense_variant 3/161 NM_000218.3 P1P51787-1
KCNQ1ENST00000335475.6 linkuse as main transcriptc.160C>T p.Arg54Cys missense_variant 3/161 P51787-2
KCNQ1ENST00000496887.7 linkuse as main transcriptc.280C>T p.Arg94Cys missense_variant 4/165
KCNQ1ENST00000646564.2 linkuse as main transcriptc.478-12744C>T intron_variant

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152202
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:
0.000192
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:
0.0000160
AC:
4
AN:
249710
Hom.:
0
AF XY:
0.0000295
AC XY:
4
AN XY:
135404
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000177
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000199
AC:
29
AN:
1460392
Hom.:
0
Cov.:
32
AF XY:
0.0000206
AC XY:
15
AN XY:
726618
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000671
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.0000192
Gnomad4 NFE exome
AF:
0.0000198
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152202
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74350
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.000192
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000151
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingAll of Us Research Program, National Institutes of HealthJan 11, 2024Variant of Uncertain Significance due to insufficient evidence: This missense variant is located in the cytoplasmic linker between transmembrane domain S2 and S3 domain of the KCNQ1 protein. Computational prediction tools and conservation analyses suggest that this variant may have deleterious impact on the protein function. Computational splicing tools suggest that this variant may not impact RNA splicing. An experimental functional study has suggested that this variant may increase current amplitudes compared with wild type channels (PMID: 24947509). However, clinical significance of this finding is not clear. This variant has not been reported in individuals affected with cardiovascular disorders in the literature. This variant has been identified in 5/275944 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Available evidence is insufficient to determine the pathogenicity of this variant conclusively. -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 24, 2024This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 181 of the KCNQ1 protein (p.Arg181Cys). This variant is present in population databases (rs199473395, gnomAD 0.005%). This variant has not been reported in the literature in individuals affected with KCNQ1-related conditions. ClinVar contains an entry for this variant (Variation ID: 67079). 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: 24947509). 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. -
Long QT syndrome 1 Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingCenter for Genomic Medicine, King Faisal Specialist Hospital and Research CenterMar 26, 2024- -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsJan 04, 2024The p.R181C variant (also known as c.541C>T), located in coding exon 3 of the KCNQ1 gene, results from a C to T substitution at nucleotide position 541. The arginine at codon 181 is replaced by cysteine, an amino acid with highly dissimilar properties. This variant has been detected in a control from a long QT syndrome study; however, clinical details were limited (Kapa S et al. Circulation, 2009 Nov;120:1752-60). One functional study has suggested that this variant may result in increased channel current compared to wild type (Eckey K et al. J Biol Chem. 2014 Aug;289(33):22749-22758). 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 limited at this time, the clinical significance of this alteration remains unclear. -
Cardiac arrhythmia Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingColor Diagnostics, LLC DBA Color HealthJan 19, 2023This missense variant replaces arginine with cysteine at codon 181 of the KCNQ1 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). A functional study has suggested that this variant may increase current amplitudes compared with wild-type channels (PMID: 24947509). This variant has been reported in individuals affected with hypertrophic cardiomyopathy (PMID: 25351510). This variant has been identified in 6/281096 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. -
not provided Other:1
not provided, no classification providedliterature onlyCardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust-This variant has been reported in the following publications (PMID:19841300). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.77
BayesDel_addAF
Pathogenic
0.42
D
BayesDel_noAF
Pathogenic
0.45
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.98
.;D;.
Eigen
Uncertain
0.35
Eigen_PC
Uncertain
0.34
FATHMM_MKL
Uncertain
0.79
D
LIST_S2
Pathogenic
0.98
D;D;D
M_CAP
Pathogenic
0.77
D
MetaRNN
Pathogenic
0.95
D;D;D
MetaSVM
Pathogenic
0.92
D
MutationAssessor
Uncertain
2.1
.;M;.
MutationTaster
Benign
1.0
D;D
PrimateAI
Uncertain
0.78
T
PROVEAN
Pathogenic
-7.2
D;D;D
REVEL
Pathogenic
0.84
Sift
Benign
0.092
T;T;T
Sift4G
Benign
0.17
T;T;D
Polyphen
0.88
.;P;.
Vest4
0.93, 0.91
MutPred
0.84
.;Loss of MoRF binding (P = 0.007);.;
MVP
0.95
MPC
1.4
ClinPred
0.93
D
GERP RS
4.4
Varity_R
0.82
gMVP
0.96

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.070
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: rs199473395; hg19: chr11-2591921; API