rs199472728

Positions:

chr11-2572885-A-G

Variant summary

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

The NM_000218.3(KCNQ1):c.820A>G(p.Ile274Val) variant causes a missense change. The variant allele was found at a frequency of 0.000199 in 1,613,666 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I274N) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00021 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:7B:3O:1

Conservation

PhyloP100: 6.90

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 11 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_000218.3

PM5

Other missense variant is known to change same aminoacid residue: Variant chr11-2572886-T-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1711271.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.820A>G	p.Ile274Val	missense_variant	6/16	ENST00000155840.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ1	ENST00000155840.12 linkuse as main transcript	c.820A>G	p.Ile274Val	missense_variant	6/16	1	NM_000218.3	P1	P51787-1
KCNQ1	ENST00000335475.6 linkuse as main transcript	c.439A>G	p.Ile147Val	missense_variant	6/16	1			P51787-2
KCNQ1	ENST00000496887.7 linkuse as main transcript	c.559A>G	p.Ile187Val	missense_variant	7/16	5
KCNQ1	ENST00000646564.2 linkuse as main transcript	c.478-10550A>G		intron_variant

Frequencies

GnomAD3 genomes

AF:

0.000125

AC:

AN:

152214

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

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:

0.000376

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000180

AC:

AN:

250462

Hom.:

AF XY:

0.000206

AC XY:

AN XY:

135708

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:

0.00

Gnomad FIN exome

AF:

0.000694

Gnomad NFE exome

AF:

0.000257

Gnomad OTH exome

AF:

0.000164

GnomAD4 exome

AF:

0.000207

AC:

302

AN:

1461452

Hom.:

Cov.:

AF XY:

0.000210

AC XY:

153

AN XY:

727044

show subpopulations

Gnomad4 AFR exome

AF:

0.000119

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:

0.000490

Gnomad4 NFE exome

AF:

0.000236

Gnomad4 OTH exome

AF:

0.000166

GnomAD4 genome

AF:

0.000125

AC:

AN:

152214

Hom.:

Cov.:

AF XY:

0.000161

AC XY:

AN XY:

74378

show subpopulations

Gnomad4 AFR

AF:

0.000121

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.000376

Gnomad4 NFE

AF:

0.000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000136

Hom.:

Bravo

AF:

0.000110

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.000255

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:7Benign:3Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Long QT syndrome

Uncertain:1Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Invitae	Nov 11, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Feb 05, 2024	This missense variant replaces isoleucine with valine at codon 274 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). To our knowledge, functional studies have not been performed for this variant. Whole-cell patch clamp experiments using transfected CHO cells have suggested that this variant may impact function (PMID: 18222468, 24920132). However, clinical relevance of these observations is not clear. This variant has been reported in individuals affected with sudden infant death syndrome (PMID: 17210839, 18222468) and long QT syndrome (PMID: 17470695). This variant has also been identified in 49/281866 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. -

SUDDEN INFANT DEATH SYNDROME

Pathogenic:1

Likely pathogenic, no assertion criteria provided

research

CSER _CC_NCGL, University of Washington

Jun 01, 2014

- -

Long QT syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Dec 12, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Apr 07, 2020

Variant classified as Uncertain Significance - Favor Benign. The p.Ile274Val variant in KCNQ1 has been reported in the heterozygous state in 1 individual with hearing loss where another variant was not identified on the second copy of the KCNQ1 gene, in at least 1 individual with a prolonged QT interval, and 1 individual with sudden infant death syndrome (Moss 2007, Arnestad 2007, Kapplinger 2009, Amin 2012, Goldenberg 2011, LMM data). This variant has also been reported by other clinical laboratories in ClinVar (Variation ID 67109) and has been identified in 0.02% (30/126372) of European chromosomes and 0.06% (16/25754) of Finnish chromosomes, including 1 homozygote, by gnomAD (http://gnomad.broadinstitute.org/). An in vitro patch-clamp study, in which p.Ile274Val was expressed in cultured mammalian cells, suggested that the variant may impact protein function (Rhodes 2008); ; however, these types of assays may not accurately represent biological function. Computational prediction tools and conservation analysis suggest that the p.Ile274Val variant may impact the protein, though this information is not predictive enough to determine pathogenicity. In summary, the clinical significance of the p.Ile274Val variant is uncertain. ACMG/AMP Criteria applied: PP3, PS3_Supporting. -

Atrial fibrillation, familial, 3

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Dec 12, 2017

Jervell and Lange-Nielsen syndrome 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Dec 12, 2017

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 07, 2022

Published functional studies suggest the p.(I274V) variant may alter protein interactions under various experimental conditions; however, it is not known whether these findings are biological or clinically relevant in vivo (Rhodes et al., 2008), and one study showed the alterations were not statistically significant (Huang et al., 2021); In silico analysis supports that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 29197658, 35508187, 33600800, 25637381, 19490272, 19716085, 17999538, 17470695, 17210839, 30420954, 32048431, 31043699, 30615648, 29501667, 18222468, 23465283) -

Cardiac arrhythmia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Nov 15, 2023

This missense variant replaces isoleucine with valine at codon 274 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). To our knowledge, functional studies have not been performed for this variant. Whole-cell patch clamp experiments using transfected CHO cells have suggested that this variant may impact function (PMID: 18222468, 24920132). However, clinical relevance of these observations is not clear. This variant has been reported in individuals affected with sudden infant death syndrome (PMID: 17210839, 18222468) and long QT syndrome (PMID: 17470695). This variant has also been identified in 49/281866 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. -

Short QT syndrome type 2

Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Dec 12, 2017

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to rule this variant out of causing disease. Therefore, this variant is classified as benign. -

Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 28, 2020

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Congenital long QT syndrome

Other:1

not provided, no classification provided

literature only

Cardiovascular 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:17210839;PMID:19716085;PMID:17999538;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

Uncertain

0.45

BayesDel_addAF

Pathogenic

0.31

BayesDel_noAF

Pathogenic

0.50

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Uncertain

0.42

Eigen_PC

Uncertain

0.38

FATHMM_MKL

Uncertain

0.95

LIST_S2

Uncertain

0.95

D;D;D

M_CAP

Pathogenic

0.88

MetaRNN

Uncertain

0.49

T;T;T

MetaSVM

Pathogenic

1.1

MutationTaster

Benign

1.0

D;D

PrimateAI

Uncertain

0.78

PROVEAN

Benign

-0.98

N;N;N

REVEL

Pathogenic

0.85

Sift

Pathogenic

0.0

D;D;D

Sift4G

Uncertain

0.0030

D;D;T

Polyphen

0.89, 1.0

.;P;D

Vest4

0.93, 0.89

MVP

0.96

MPC

1.1

ClinPred

0.18

GERP RS

3.7

Varity_R

0.88

gMVP

0.95

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