rs199472788

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1PP2PP3_Strong

The NM_000218.3(KCNQ1):​c.1556G>A​(p.Arg519His) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000254 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R519C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

12
5
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:10B:1O:1

Conservation

PhyloP100: 9.45

Publications

14 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: Likely_pathogenic. The variant received 7 ACMG points.

PM1
In a hotspot region, there are 12 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 16 uncertain in NM_000218.3
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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.958

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ1NM_000218.3 linkc.1556G>A p.Arg519His missense_variant Exon 12 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.1556G>A p.Arg519His missense_variant Exon 12 of 16 1 NM_000218.3 ENSP00000155840.2 P51787-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152110
Hom.:
0
Cov.:
32
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:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000239
AC:
6
AN:
251404
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000267
AC:
39
AN:
1461810
Hom.:
0
Cov.:
31
AF XY:
0.0000275
AC XY:
20
AN XY:
727208
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.000453
AC:
18
AN:
39700
South Asian (SAS)
AF:
0.0000464
AC:
4
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53398
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000144
AC:
16
AN:
1111956
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
3
7
10
14
17
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

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:
152110
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74296
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41420
American (AMR)
AF:
0.00
AC:
0
AN:
15262
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5160
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.625
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000261
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000330
AC:
4

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:10Benign:1Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Long QT syndrome 1 Uncertain:2
Jun 02, 2023
Mendelics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 24, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Long QT syndrome Uncertain:2
Aug 30, 2024
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 arginine with histidine 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 region of the c-terminal cytoplasmic domain. Rare nontruncating variants in this region (a.a. 509-575) have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). A functional study has shown that this variant causes a reduction in channel peak current density in transfected cells (PMID: 34930020). This variant has been reported in three unrelated individuals affected with long QT syndrome (PMID: 26118460), as well as in two healthy individuals (PMID: 19841300, 14661677). This variant has been identified in 7/282764 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Although there is a suspicion for a pathogenic role, 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. -

Dec 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 519 of the KCNQ1 protein (p.Arg519His). This variant is present in population databases (rs199472788, gnomAD 0.006%). This missense change has been observed in individual(s) with long QT syndrome (PMID: 14661677, 19841300, 26118460, 32893267, 34930020). ClinVar contains an entry for this variant (Variation ID: 67038). Invitae Evidence 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 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. Experimental studies have shown that this missense change affects KCNQ1 function (PMID: 34930020). 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 provided Uncertain:1Other:1
Aug 24, 2018
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
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 in the following publications (PMID:14661677;PMID:19841300). -

Atrial fibrillation, familial, 3 Uncertain:1
Aug 24, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

Jervell and Lange-Nielsen syndrome 1 Uncertain:1
Aug 24, 2017
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

KCNQ1-related disorder Uncertain:1
Jul 11, 2023
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The KCNQ1 c.1556G>A variant is predicted to result in the amino acid substitution p.Arg519His. This variant was reported in an individual with long QT syndrome (Itoh et al 2015. PubMed ID: 26118460). This variant is reported in 0.0065% of alleles in individuals of South Asian descent in gnomAD (http://gnomad.broadinstitute.org/variant/11-2790115-G-A). At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Cardiovascular phenotype Uncertain:1
Mar 15, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1556G>A (p.R519H) alteration is located in exon 12 (coding exon 12) of the KCNQ1 gene. This alteration results from a G to A substitution at nucleotide position 1556, causing the arginine (R) at amino acid position 519 to be replaced by a histidine (H). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Cardiac arrhythmia Uncertain:1
Jan 29, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces arginine with histidine 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 region of the c-terminal cytoplasmic domain. Rare nontruncating variants in this region (a.a. 509-575) have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). A functional study has shown that this variant causes a reduction in channel peak current density in transfected cells (PMID: 34930020). This variant has been reported in three unrelated individuals affected with long QT syndrome (PMID: 26118460), as well as in two healthy individuals (PMID: 19841300, 14661677). This variant has been identified in 7/282764 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. -

Short QT syndrome type 2 Benign:1
Aug 24, 2017
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.42
CardioboostArm
Pathogenic
0.99
BayesDel_addAF
Pathogenic
0.22
D
BayesDel_noAF
Pathogenic
0.26
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.97
D;.;.
Eigen
Pathogenic
0.73
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Pathogenic
0.98
D;D;D
M_CAP
Pathogenic
0.85
D
MetaRNN
Pathogenic
0.96
D;D;D
MetaSVM
Pathogenic
1.0
D
MutationAssessor
Uncertain
2.4
M;.;.
PhyloP100
9.4
PrimateAI
Uncertain
0.78
T
PROVEAN
Uncertain
-3.7
D;.;D
REVEL
Pathogenic
0.88
Sift
Benign
0.065
T;.;D
Sift4G
Benign
0.13
T;.;T
Polyphen
1.0
D;.;D
Vest4
0.94
MutPred
0.81
Loss of helix (P = 0.1299);.;.;
MVP
0.99
MPC
1.3
ClinPred
0.93
D
GERP RS
4.3
Varity_R
0.40
gMVP
0.94
Mutation Taster
=2/98
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

Other links and lift over

dbSNP: rs199472788; hg19: chr11-2790115; API