11-2768884-C-T

Position:

chr11-2768884-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PP3_Strong

The NM_000218.3(KCNQ1):c.1555C>T(p.Arg519Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000217 in 1,613,920 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. R519H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:6O:1

Conservation

PhyloP100: 3.74

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 Likely_pathogenic. Variant got 6 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, 10 uncertain in NM_000218.3

PP3

MetaRNN computational evidence supports a deleterious effect, 0.973

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ1	NM_000218.3 linkuse as main transcript	c.1555C>T	p.Arg519Cys	missense_variant	12/16	ENST00000155840.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ1	ENST00000155840.12 linkuse as main transcript	c.1555C>T	p.Arg519Cys	missense_variant	12/16	1	NM_000218.3	P1	P51787-1
KCNQ1	ENST00000335475.6 linkuse as main transcript	c.1174C>T	p.Arg392Cys	missense_variant	12/16	1			P51787-2
KCNQ1	ENST00000496887.7 linkuse as main transcript	c.1198C>T	p.Arg400Cys	missense_variant	12/16	5
KCNQ1	ENST00000646564.2 linkuse as main transcript	c.1015C>T	p.Arg339Cys	missense_variant	7/11

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152098

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:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000438

AC:

AN:

251406

Hom.:

AF XY:

0.0000589

AC XY:

AN XY:

135890

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:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000704

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000212

AC:

AN:

1461822

Hom.:

Cov.:

AF XY:

0.0000206

AC XY:

AN XY:

727204

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000207

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152098

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74274

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:

0.0000588

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000444

Hom.:

Bravo

AF:

0.0000227

ExAC

AF:

0.0000494

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:6Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Long QT syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Sep 22, 2023	This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 519 of the KCNQ1 protein (p.Arg519Cys). This variant is present in population databases (rs199472787, gnomAD 0.006%). This missense change has been observed in individual(s) with long QT syndrome (PMID: 12566525). ClinVar contains an entry for this variant (Variation ID: 67037). 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 does not substantially affect KCNQ1 function (PMID: 24190995). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Nov 02, 2023	This missense variant replaces arginine with cysteine at codon 519 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). This variant is found within a highly conserved C-terminus region (a.a. 509-575). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in two individuals affected with long QT syndrome (PMID: 12566525, Kostereva 2022 DOI: 10.35336/VA-2022-1-02). This variant has been identified in 11/251406 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 specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jun 23, 2016

Variant identified in a genome or exome case(s) and assessed due to predicted null impact of the variant or pathogenic assertions in the literature or databases. Disclaimer: This variant has not undergone full assessment. The following are preliminary notes: Reported in 1-2 probands; ClinVar: 1 Pathogenic -

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

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 19, 2017

The c.1555C>T (p.R519C) alteration is located in exon 12 (coding exon 12) of the KCNQ1 gene. This alteration results from a C to T substitution at nucleotide position 1555, causing the arginine (R) at amino acid position 519 to be replaced by a cysteine (C). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Oct 22, 2023

This missense variant replaces arginine with cysteine at codon 519 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). This variant is found within a highly conserved C-terminus region (a.a. 509-575). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in two individuals affected with long QT syndrome (PMID: 12566525, Kostereva 2022 DOI: 10.35336/VA-2022-1-02). This variant has been identified in 11/251406 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. -

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:12566525). 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

0.65

BayesDel_addAF

Pathogenic

0.35

BayesDel_noAF

Pathogenic

0.43

CADD

Pathogenic

DANN

Pathogenic

1.0

DEOGEN2

Pathogenic

0.96

D;.;.

Eigen

Uncertain

0.58

Eigen_PC

Uncertain

0.51

FATHMM_MKL

Benign

0.70

LIST_S2

Pathogenic

0.99

D;D;D

M_CAP

Pathogenic

0.89

MetaRNN

Pathogenic

0.97

D;D;D

MetaSVM

Pathogenic

1.0

MutationAssessor

Uncertain

2.4

M;.;.

MutationTaster

Benign

1.0

D;D

PrimateAI

Pathogenic

0.82

PROVEAN

Pathogenic

-6.0

D;.;D

REVEL

Pathogenic

0.90

Sift

Benign

0.034

D;.;D

Sift4G

Uncertain

0.043

D;.;D

Polyphen

1.0

D;.;D

Vest4

0.91

MutPred

0.83

Gain of sheet (P = 0.0477);.;.;

MVP

0.99

MPC

1.4

ClinPred

0.78

GERP RS

4.3

Varity_R

0.59

gMVP

0.97

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