rs775608046

Variant summary

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

The NM_000218.3(KCNQ1):c.1885G>A(p.Gly629Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000381 in 1,574,258 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign 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. G629V) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000037 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:8

Conservation

PhyloP100: -0.0150

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=0.15049699).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ1	NM_000218.3 linkuse as main transcript	c.1885G>A	p.Gly629Ser	missense_variant	16/16	ENST00000155840.12
KCNQ1-AS1	NR_130721.1 linkuse as main transcript	n.778-7415C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ1	ENST00000155840.12 linkuse as main transcript	c.1885G>A	p.Gly629Ser	missense_variant	16/16	1	NM_000218.3	P1	P51787-1
KCNQ1-AS1	ENST00000440887.2 linkuse as main transcript	n.777-7415C>T		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes

AF:

0.0000460

AC:

AN:

152148

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000724

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:

0.0000490

AC:

AN:

183736

Hom.:

AF XY:

0.0000604

AC XY:

AN XY:

99376

show subpopulations

Gnomad AFR exome

AF:

0.0000976

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000121

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000660

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000373

AC:

AN:

1422110

Hom.:

Cov.:

AF XY:

0.0000355

AC XY:

AN XY:

703746

show subpopulations

Gnomad4 AFR exome

AF:

0.0000919

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000493

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000403

Gnomad4 OTH exome

AF:

0.0000340

GnomAD4 genome

AF:

0.0000460

AC:

AN:

152148

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74334

show subpopulations

Gnomad4 AFR

AF:

0.0000724

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

Bravo

AF:

0.0000567

ExAC

AF:

0.0000507

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:8

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	All of Us Research Program, National Institutes of Health	Feb 05, 2024	This missense variant replaces glycine with serine at codon 629 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). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with long QT syndrome (PMID 27871843), Brugada syndrome (PMID: 29255176), or hypertrophic cardiomyopathy (PMID: 25351510). This variant has been identified in 11/215064 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 27, 2021	This sequence change replaces glycine with serine at codon 629 of the KCNQ1 protein (p.Gly629Ser). The glycine residue is weakly conserved and there is a small physicochemical difference between glycine and serine. This variant is present in population databases (rs775608046, ExAC 0.04%). This missense change has been observed in individual(s) with long QT syndrome (PMID: 27871843). ClinVar contains an entry for this variant (Variation ID: 427960). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The serine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect 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. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

May 23, 2019

The KCNQ1 c.1885G>A; p.Gly629Ser variant (rs775608046) is reported in the literature in an individual affected with long QT syndrome, though it was not demonstrated to be disease-causing (Chae 2017). This variant is found in the general population with a low overall allele frequency of 0.005% (11/215064 alleles) in the Genome Aggregation Database. The glycine at codon 629 is weakly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is tolerated. However, due to limited information, the clinical significance of the p.Gly629Ser variant is uncertain at this time. References: Chae H et al. Considerations when using next-generation sequencing for genetic diagnosis of long-QT syndrome in the clinical testing laboratory. Clin Chim Acta. 2017 Jan;464:128-135. -

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

Dec 08, 2021

- -

Brugada syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Center for Human Genetics, University of Leuven

Apr 30, 2017

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jun 27, 2019

Reported in association with hypertrophic cardiomyopathy, Brugada syndrome, and LQTS (Lopes et al., 2015; Robyns et al., 2017; Chae et al., 2017); Reported in ClinVar as a variant of uncertain significance (ClinVar Variant ID# 427960; Landrum et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 27871843, 25351510, 29255176) -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 26, 2023

The p.G629S variant (also known as c.1885G>A), located in coding exon 16 of the KCNQ1 gene, results from a G to A substitution at nucleotide position 1885. The glycine at codon 629 is replaced by serine, an amino acid with similar properties. This alteration was reported in one patient with long QT syndrome, though specific clinical details were limited (Chae H et al. Clin Chim Acta, 2017 Jan;464:128-135). This amino acid position is not well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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 submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Jul 28, 2023

This missense variant replaces glycine with serine at codon 629 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). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with long QT syndrome (PMID 27871843), Brugada syndrome (PMID: 29255176), or hypertrophic cardiomyopathy (PMID: 25351510). This variant has been identified in 11/215064 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.077

CardioboostArm

Benign

0.00045

BayesDel_addAF

Uncertain

0.024

BayesDel_noAF

Uncertain

0.020

Cadd

Benign

1.6

Dann

Benign

0.59

DEOGEN2

Benign

0.32

T;.;.

Eigen

Benign

-1.4

Eigen_PC

Benign

-1.5

FATHMM_MKL

Benign

0.022

LIST_S2

Benign

0.41

T;T;T

M_CAP

Pathogenic

0.66

MetaRNN

Benign

0.15

T;T;T

MetaSVM

Pathogenic

0.96

MutationAssessor

Benign

1.4

L;.;.

MutationTaster

Benign

1.0

N;N

PrimateAI

Benign

0.40

PROVEAN

Benign

0.29

N;N;.

REVEL

Uncertain

0.57

Sift

Benign

0.69

T;T;.

Sift4G

Benign

0.79

T;T;.

Polyphen

0.39

B;.;.

Vest4

0.14

MutPred

0.29

Gain of glycosylation at G629 (P = 0.0028);.;.;

MVP

0.75

MPC

0.37

ClinPred

0.015

GERP RS

-1.1

Varity_R

0.028

gMVP

0.38

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