rs199956744

Positions:

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1PM5

The NM_000218.3(KCNQ1):c.721G>A(p.Val241Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000267 in 1,612,752 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. V241G) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 6.33

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]

KCNQ1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PM1

In a hotspot region, there are 7 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 chr11-2572050-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 405255.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ1	NM_000218.3 linkuse as main transcript	c.721G>A	p.Val241Ile	missense_variant	5/16	ENST00000155840.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ1	ENST00000155840.12 linkuse as main transcript	c.721G>A	p.Val241Ile	missense_variant	5/16	1	NM_000218.3	P1	P51787-1
KCNQ1	ENST00000335475.6 linkuse as main transcript	c.340G>A	p.Val114Ile	missense_variant	5/16	1			P51787-2
KCNQ1	ENST00000496887.7 linkuse as main transcript	c.460G>A	p.Val154Ile	missense_variant	6/16	5
KCNQ1	ENST00000646564.2 linkuse as main transcript	c.478-11385G>A		intron_variant

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

152090

Hom.:

Cov.:

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:

0.00

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000120

AC:

AN:

249108

Hom.:

AF XY:

0.0000222

AC XY:

AN XY:

135238

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000290

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000890

Gnomad OTH exome

AF:

0.000165

GnomAD4 exome

AF:

0.0000288

AC:

AN:

1460662

Hom.:

Cov.:

AF XY:

0.0000289

AC XY:

AN XY:

726660

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000333

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.00000658

AC:

AN:

152090

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74294

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:

0.00

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000113

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:3

Uncertain significance, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Uncertain significance, no assertion criteria provided	clinical testing	Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+	-	- -
Uncertain significance, criteria provided, single submitter	research	Biesecker Lab/Clinical Genomics Section, National Institutes of Health	Jun 24, 2013	- -

Long QT syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 04, 2023

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 241 of the KCNQ1 protein (p.Val241Ile). This variant is present in population databases (rs199956744, gnomAD 0.003%). This missense change has been observed in individual(s) with long QT syndrome (PMID: 26669661). ClinVar contains an entry for this variant (Variation ID: 191477). 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. Experimental studies have shown that this missense change affects KCNQ1 function (PMID: 30571187). 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. -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 05, 2020

The p.V241I variant (also known as c.721G>A), located in coding exon 5 of the KCNQ1 gene, results from a G to A substitution at nucleotide position 721. The valine at codon 241 is replaced by isoleucine, an amino acid with highly similar properties. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.44

BayesDel_addAF

Pathogenic

0.25

BayesDel_noAF

Pathogenic

0.20

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.72

.;D;.

Eigen

Uncertain

0.36

Eigen_PC

Uncertain

0.32

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Uncertain

0.94

D;D;D

M_CAP

Pathogenic

0.41

MetaRNN

Uncertain

0.73

D;D;D

MetaSVM

Pathogenic

0.98

MutationAssessor

Benign

1.3

.;L;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.75

PROVEAN

Benign

-0.82

N;N;N

REVEL

Pathogenic

0.69

Sift

Benign

0.20

T;T;T

Sift4G

Benign

0.37

T;T;T

Polyphen

0.96, 1.0

.;D;D

Vest4

0.52

MutPred

0.57

.;Loss of helix (P = 0.0558);.;

MVP

0.96

MPC

0.73

ClinPred

0.74

GERP RS

4.3

Varity_R

0.48

gMVP

0.88

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over