rs1057518902

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2PP2BP4

The NM_000218.3(KCNQ1):​c.1349A>G​(p.Glu450Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,460,998 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E450K) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

1
7
12

Clinical Significance

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

Conservation

PhyloP100: 4.28

Publications

1 publications found
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 Gene-Disease associations (from GenCC):
  • long QT syndrome
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • long QT syndrome 1
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • Jervell and Lange-Nielsen syndrome
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • Jervell and Lange-Nielsen syndrome 1
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), G2P
  • atrial fibrillation, familial, 3
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • short QT syndrome
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • short QT syndrome type 2
    Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
  • familial atrial fibrillation
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Jervell and Lange-Nielsen syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hypertrophic cardiomyopathy
    Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 212 curated pathogenic missense variants (we use a threshold of 10). The gene has 12 curated benign missense variants. Gene score misZ: 1.8321 (below the threshold of 3.09). Trascript score misZ: 0.90233 (below the threshold of 3.09). GenCC associations: The gene is linked to short QT syndrome type 2, long QT syndrome 1, Jervell and Lange-Nielsen syndrome 1, long QT syndrome, short QT syndrome, Jervell and Lange-Nielsen syndrome, hypertrophic cardiomyopathy, familial atrial fibrillation, atrial fibrillation, familial, 3.
BP4
Computational evidence support a benign effect (MetaRNN=0.2796632).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ1NM_000218.3 linkc.1349A>G p.Glu450Gly missense_variant Exon 10 of 16 ENST00000155840.12 NP_000209.2 P51787-1Q96AI9

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNQ1ENST00000155840.12 linkc.1349A>G p.Glu450Gly missense_variant Exon 10 of 16 1 NM_000218.3 ENSP00000155840.2 P51787-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1460998
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
726772
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33470
American (AMR)
AF:
0.00
AC:
0
AN:
44696
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86188
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53022
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5504
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111932
Other (OTH)
AF:
0.00
AC:
0
AN:
60352
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cardiac arrhythmia Uncertain:2
Feb 17, 2014
Centre for Mendelian Genomics, University Medical Centre Ljubljana
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Sep 09, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces glutamic acid with glycine at codon 450 of the KCNQ1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with KCNQ1-related disorders in the literature. This variant has not been identified 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. -

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
Sep 21, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Apr 18, 2022
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Not observed in large population cohorts (gnomAD); In silico analysis supports that this missense variant does not alter protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Long QT syndrome Uncertain:1
May 09, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. 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) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on KCNQ1 protein function. ClinVar contains an entry for this variant (Variation ID: 374106). This sequence change replaces glutamic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 450 of the KCNQ1 protein (p.Glu450Gly). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with KCNQ1-related conditions. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.079
CardioboostArm
Benign
0.0034
BayesDel_addAF
Pathogenic
0.18
D
BayesDel_noAF
Uncertain
0.020
CADD
Benign
19
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.44
T;.;.
Eigen
Benign
-0.62
Eigen_PC
Benign
-0.51
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Benign
0.61
T;T;T
M_CAP
Uncertain
0.27
D
MetaRNN
Benign
0.28
T;T;T
MetaSVM
Uncertain
0.66
D
MutationAssessor
Benign
0.90
L;.;.
PhyloP100
4.3
PrimateAI
Benign
0.33
T
PROVEAN
Benign
-1.8
N;.;N
REVEL
Uncertain
0.58
Sift
Benign
0.17
T;.;T
Sift4G
Benign
0.30
T;.;T
Polyphen
0.10
B;.;B
Vest4
0.23
MutPred
0.27
Gain of sheet (P = 0.0266);.;.;
MVP
0.94
MPC
0.43
ClinPred
0.32
T
GERP RS
3.9
Varity_R
0.078
gMVP
0.46
Mutation Taster
=72/28
polymorphism

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

Other links and lift over

dbSNP: rs1057518902; hg19: chr11-2610040; API