rs199473449

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1PM5PP2PP3_Strong

The NM_000218.3(KCNQ1):​c.397G>A​(p.Val133Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000744 in 1,613,930 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. V133A) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 34)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

7
9
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4O:1

Conservation

PhyloP100: 8.09
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]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_000218.3
PM5
Other missense variant is known to change same aminoacid residue: Variant chr11-2527938-G-T is described in Lovd as [Likely_pathogenic].
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 hypertrophic cardiomyopathy, long QT syndrome, Jervell and Lange-Nielsen syndrome 1, short QT syndrome, atrial fibrillation, familial, 3, short QT syndrome type 2, familial atrial fibrillation, long QT syndrome 1, Jervell and Lange-Nielsen syndrome.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.951

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ1NM_000218.3 linkc.397G>A p.Val133Ile missense_variant Exon 2 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.397G>A p.Val133Ile missense_variant Exon 2 of 16 1 NM_000218.3 ENSP00000155840.2 P51787-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152180
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251392
AF XY:
0.00000736
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461750
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727180
show subpopulations
Gnomad4 AFR exome
AF:
0.00
AC:
0
AN:
33476
Gnomad4 AMR exome
AF:
0.0000224
AC:
1
AN:
44722
Gnomad4 ASJ exome
AF:
0.00
AC:
0
AN:
26136
Gnomad4 EAS exome
AF:
0.00
AC:
0
AN:
39698
Gnomad4 SAS exome
AF:
0.00
AC:
0
AN:
86256
Gnomad4 FIN exome
AF:
0.00
AC:
0
AN:
53342
Gnomad4 NFE exome
AF:
0.00000719
AC:
8
AN:
1111958
Gnomad4 Remaining exome
AF:
0.0000166
AC:
1
AN:
60394
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152180
Hom.:
0
Cov.:
34
AF XY:
0.00
AC XY:
0
AN XY:
74324
show subpopulations
Gnomad4 AFR
AF:
0.0000241
AC:
0.0000241313
AN:
0.0000241313
Gnomad4 AMR
AF:
0.00
AC:
0
AN:
0
Gnomad4 ASJ
AF:
0.00
AC:
0
AN:
0
Gnomad4 EAS
AF:
0.00
AC:
0
AN:
0
Gnomad4 SAS
AF:
0.00
AC:
0
AN:
0
Gnomad4 FIN
AF:
0.00
AC:
0
AN:
0
Gnomad4 NFE
AF:
0.0000147
AC:
0.0000147007
AN:
0.0000147007
Gnomad4 OTH
AF:
0.00
AC:
0
AN:
0
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:2
Dec 07, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 133 of the KCNQ1 protein (p.Val133Ile). This variant is present in population databases (rs199473449, gnomAD 0.0009%). This missense change has been observed in individual(s) with long QT syndrome (PMID: 12877697). ClinVar contains an entry for this variant (Variation ID: 67069). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. Experimental studies have shown that this missense change does not substantially affect KCNQ1 function (PMID: 27810088, 29532034, 30571187). 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. -

May 04, 2023
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces valine with isoleucine at codon 133 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). Functional studies have shown that this variant has no substantial impact on channel function in intro (PMID: 27810088, 29532034, 30571187, 31518351). This variant has been reported in a few individuals affected with long QT syndrome or other cardiovascular disease (PMID: 15840476, 19716085, 31696929), and in multiple individuals from a family, none of whom had indications of long QT syndrome (PMID: 27810088). This variant has been identified in 1/251392 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. -

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 28, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiac arrhythmia Uncertain:1
Mar 25, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces valine with isoleucine at codon 133 of the KCNQ1 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function. Functional studies have shown that this variant has no substantial impact on channel function in intro (PMID: 27810088, 29532034, 30571187, 31518351). This variant has been reported in a few individuals affected with long QT syndrome or other cardiovascular disease (PMID: 15840476, 19716085, 31696929). This variant has also been observed in multiple individuals from a family, who were all unaffected with long QT syndrome (PMID: 27810088). This variant has been identified in 1/251392 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:12877697;PMID:15840476;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
Uncertain
0.45
CardioboostArm
Pathogenic
0.90
BayesDel_addAF
Pathogenic
0.45
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.77
.;D;.;.;.
Eigen
Uncertain
0.62
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Uncertain
0.96
D;D;D;D;.
M_CAP
Pathogenic
0.46
D
MetaRNN
Pathogenic
0.95
D;D;D;D;D
MetaSVM
Pathogenic
0.97
D
MutationAssessor
Uncertain
2.0
.;M;.;.;.
PrimateAI
Uncertain
0.72
T
PROVEAN
Benign
-0.83
N;N;.;N;N
REVEL
Pathogenic
0.78
Sift
Benign
0.081
T;D;.;D;.
Sift4G
Benign
0.082
T;D;.;D;D
Polyphen
0.99
.;D;.;.;.
Vest4
0.94, 0.79
MutPred
0.85
.;Loss of catalytic residue at V133 (P = 0.098);.;.;.;
MVP
0.96
MPC
1.7
ClinPred
0.97
D
GERP RS
3.5
Varity_R
0.62
gMVP
0.89
Mutation Taster
=27/73
disease causing

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.

Other links and lift over

dbSNP: rs199473449; hg19: chr11-2549168; API