chr11-2847848-G-A

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_000218.3(KCNQ1):c.1876G>A(p.Gly626Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000267 in 1,571,048 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

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

Exomes 𝑓: 0.000028 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts P:1U:7O:1

Conservation

PhyloP100: -0.255

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:

KCNQ1-AS1 (HGNC:42790): (KCNQ1 antisense RNA 1)

KCNQ1-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.1514025).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNQ1	NM_000218.3 link	c.1876G>A	p.Gly626Ser	missense_variant	Exon 16 of 16	ENST00000155840.12	NP_000209.2	P51787-1Q96AI9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNQ1	ENST00000155840.12 link	c.1876G>A	p.Gly626Ser	missense_variant	Exon 16 of 16	1	NM_000218.3	ENSP00000155840.2		P51787-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152142

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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:

0.00

GnomAD3 exomes

AF:

0.0000111

AC:

AN:

179998

Hom.:

AF XY:

0.0000103

AC XY:

AN XY:

96966

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:

0.0000409

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000136

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000282

AC:

AN:

1418906

Hom.:

Cov.:

AF XY:

0.0000328

AC XY:

AN XY:

701828

show subpopulations

Gnomad4 AFR exome

AF:

0.000215

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000865

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000211

Gnomad4 OTH exome

AF:

0.0000341

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152142

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74332

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

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:

0.00

Alfa

AF:

0.0000680

Hom.:

Bravo

AF:

0.0000151

ClinVar

Significance: Uncertain significance

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

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:3

Feb 26, 2025

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Identified in association with LQTS and sudden infant death syndrome (SIDS) (PMID: 15840476, 19716085, 16922724, 19322600); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 21215473, 23304551, 34930020, 15840476, 16922724, 19716085, 28316956, 19322600, 31019283, 31043699) -

Nov 20, 2021

AiLife Diagnostics, AiLife Diagnostics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 30, 2022

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Gly626Ser variant in KCNQ1 has been reported in 1 individual with long QT syndrome (Tester 2005 PMID: 15840476) and in case of infant sudden death, but was also present the asymptomatic mother (Millat 2006 PMID: 16922724). It has also been identified in 0.004% (1/24468) of South Asian chromosomes by gnomAD (http://gnomad.broadinstitute.org). Computational prediction tools and conservation analyses suggest that this variant may not impact the protein, though this information is not predictive enough to rule out pathogenicity. In summary, the clinical significance of this variant is uncertain. ACMG/AMP Criteria applied: PM2_Supporting, BP4. -

Long QT syndrome 1

Pathogenic:1Uncertain:1

Nov 21, 2018

Equipe Genetique des Anomalies du Developpement, Université de Bourgogne

Significance: Pathogenic

Review Status: flagged submission

Collection Method: clinical testing

- -

Aug 01, 2023

Molecular Genetics Laboratory - Cardiogenetics, CHU de Nantes

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Long QT syndrome

Uncertain:1

Sep 27, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 626 of the KCNQ1 protein (p.Gly626Ser). 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 individual(s) with clinical features of KCNQ1-related conditions (PMID: 15840476, 19322600). ClinVar contains an entry for this variant (Variation ID: 53022). 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 not expected to disrupt KCNQ1 protein function. 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

Oct 24, 2016

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1876G>A (p.G626S) alteration is located in exon 16 (coding exon 16) of the KCNQ1 gene. This alteration results from a G to A substitution at nucleotide position 1876, causing the glycine (G) at amino acid position 626 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia

Uncertain:1

Nov 21, 2022

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces glycine with serine at codon 626 of the KCNQ1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). A functional study has shown that this variant has no significant impact on channel peak current density (PMID: 34930020). This variant has been reported in an individual affected with sudden infant death syndrome (PMID: 16922724), in an individual suspected of having long QT syndrome (PMID: 15840476), and in a few unaffected individuals (PMID: 19322600, 34930020). This variant has been identified in 2/179998 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

Cardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

This variant has been reported as associated with Long QT syndrome in the following publications (PMID:15840476;PMID:16922724;PMID:19716085). 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

Benign

0.079

BayesDel_addAF

Pathogenic

0.29

BayesDel_noAF

Pathogenic

0.18

CADD

Benign

0.40

DANN

Benign

0.68

DEOGEN2

Benign

0.27

T;.;.

Eigen

Benign

-1.5

Eigen_PC

Benign

-1.5

FATHMM_MKL

Benign

0.051

LIST_S2

Benign

0.47

T;T;T

M_CAP

Uncertain

0.17

MetaRNN

Benign

0.15

T;T;T

MetaSVM

Pathogenic

0.97

MutationAssessor

Benign

0.69

N;.;.

PrimateAI

Uncertain

0.48

PROVEAN

Benign

-0.070

N;N;.

REVEL

Uncertain

0.57

Sift

Benign

0.63

T;T;.

Sift4G

Benign

0.74

T;T;.

Polyphen

0.079

B;.;.

Vest4

0.67

MutPred

0.60

Gain of phosphorylation at G626 (P = 0.0213);.;.;

MVP

0.71

MPC

0.37

ClinPred

0.017

GERP RS

-0.34

Varity_R

0.047

gMVP

0.41

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