rs104894252

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PS1PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000218.3(KCNQ1):​c.565G>A​(p.Gly189Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,459,978 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 Likely pathogenic (★★). Another nucleotide change resulting in same amino acid change has been previously reported as Pathogenicin Lovd. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G189E) has been classified as Pathogenic.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 missense

Scores

16
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4O:1

Conservation

PhyloP100: 9.36
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 made for transcript

Verdict is Pathogenic. Variant got 22 ACMG points.

PS1
Transcript NM_000218.3 (KCNQ1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
PM1
In a helix (size 6) in uniprot entity KCNQ1_HUMAN there are 13 pathogenic changes around while only 1 benign (93%) in NM_000218.3
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr11-2570716-G-A is described in Lovd as [Pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.984
PP5
Variant 11-2570715-G-A is Pathogenic according to our data. Variant chr11-2570715-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 3114.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr11-2570715-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
KCNQ1NM_000218.3 linkuse as main transcriptc.565G>A p.Gly189Arg missense_variant 3/16 ENST00000155840.12 NP_000209.2 P51787-1Q96AI9

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
KCNQ1ENST00000155840.12 linkuse as main transcriptc.565G>A p.Gly189Arg missense_variant 3/161 NM_000218.3 ENSP00000155840.2 P51787-1
KCNQ1ENST00000335475.6 linkuse as main transcriptc.184G>A p.Gly62Arg missense_variant 3/161 ENSP00000334497.5 P51787-2
KCNQ1ENST00000496887.7 linkuse as main transcriptc.304G>A p.Gly102Arg missense_variant 4/165 ENSP00000434560.2 E9PPZ0
KCNQ1ENST00000646564.2 linkuse as main transcriptc.478-12720G>A intron_variant ENSP00000495806.2 A0A2R8YEQ9

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1459978
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
726414
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:2
Pathogenic, no assertion criteria providedclinical testingStanford Center for Inherited Cardiovascular Disease, Stanford UniversityJan 27, 2014Note this variant was found in clinical genetic testing performed by one or more labs who may also submit to ClinVar. Thus any internal case data may overlap with the internal case data of other labs. The interpretation reviewed below is that of the Stanford Center for Inherited Cardiovascular Disease. KCNQ1 p.Gly189Arg Based on the information reviewed below, we classify it as very likely disease causing. This variant has previously been reported in at least 3 unrelated individuals with LQTS. There is very strong published segregation data. Jongbloed et al. (1999) identified this variant in 2 Dutch families with LQT1. It segregated with disease in 17 affected members of one family (2 of them asymptomatic), and 3 affected members of the other (one of them asymptomatic). Wang et al. (1996) had previously reported that it segregated with disease in 3 affected siblings in a family with LQTS. Nannenberg et al. (2012) reported it in a Dutch family with LQT1 in which they traced the disease back centuries, although it is not clear if this family was included in Jongbloed et al. (According to OMIM, this variant used to be known as GLY60ARG, by Wang et al., and GLY94ARG.) Another variant at this same codon, Gly189Glu, has been reported in association with LQTS (HGMD cites Moss et al. 2007, Giudicessi et al. 2012, and another). This is a non-conservative amino acid change, resulting in the replacement of a nonpolar glycine with a positively-charged arginine with a much bulkier side-chain. Glycine at this location is highly conserved across vertebrate species (it is an alanine in a species of falcon). Variation at nearby residues has been associated with LQTS, which may support the functional importance of this region of the protein: G179S, K183R, K183M, Y184H, Y184S, G186R, G186S, L187P, R190W, R190L, R190Q, L191P, R192C, R192H, R192P, F193L, A194P, R195W, I198V, S199A (HGMD professional version as of January 17, 2014). In silico analysis with PolyPhen-2 (http://genetics.bwh.harvard.edu/pph2/) predicts the variant to be “Probably Damaging” with a score of 1.0. In vitro functional studies show that it results in a loss of KCNQ1 channel function (Wang et al. 1999, Barsheshet et al 2012). This residue is in the cytoplasmic S2-S3 linker. It is not entirely possible to tell from the location within the KCNQ1 protein if a variant causes disease. However, when Kapa et al. (2009) compared 388 “clinically definite” LQTS probands to ~1300 healthy controls, they found that LQTS cases were much more likely to have missense variants in the C-terminal cytoplasmic region of the KCNQ1 protein (amino acid residues 349-676), the pore region, transmembrane region, or linker region (residues 122-348)—rather than in the N-terminal domain (residues 1-121). Variants in the transmembrane-linker-pore domain of the protein were 24x more frequent in LQTS cases than in controls. In total the variant has not been seen in over 60,000 published controls and individuals from publicly available population datasets. The variant was not observed in published controls: 55 individuals (Jongbloed et al. 1999; didn’t check the other references). As of 6/5/2015, there is no variation at this residue listed in the NHLBI Exome Sequencing Project dataset (http://evs.gs.washington.edu/EVS/), which currently includes variant calls on ~4300 Caucasian and ~2200 African American individuals. Our patient’s ancestry is Caucasian. The phenotype of the ESP individuals is not publicly available, however the cohorts that were merged to create this dataset were all either general population samples or samples recruited for common cardiovascular disease such as hypertension. This variant was not found in 1000 Genomes (http://browser.1000genomes.org/index.htm). The variant is not present in the ExAC dataset, which currently includes variant calls on ~60,000 individuals of multiple ethnic backgrounds (Latino, European (non-Finnish), Finnish, South Asian, African & East Asian). These in -
Likely pathogenic, criteria provided, single submitterclinical testingGeneDxJun 18, 2020Identified in a patient with LQTS referred for genetic testing at GeneDx and observed in association with LQTS in the published literature (Wang et al., 1996; Wang et al., 1999; Jongbloed et al., 1999; Moss et al., 2007; Goldenberg et al., 2011; Nannenberg et al., 2012; Barsheshet et al., 2012); Published functional studies suggest damaging effect with loss of function but little dominant-negative impact (Wang et al., 1999) and reduction in normalized current (Barasheshet et al., 2012); Not observed in large population cohorts (Lek et al., 2016); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 22456477, 8528244, 10220144, 22373669, 27807201, 17470695, 21185501, 10376919) -
Long QT syndrome 1 Pathogenic:1
Pathogenic, no assertion criteria providedliterature onlyOMIMJan 01, 1999- -
Long QT syndrome Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpOct 28, 2020For these reasons, this variant has been classified as Pathogenic. This variant has been reported to affect KCNQ1 protein function (PMID: 10376919, 22456477). This variant has been observed to segregate with long QT syndrome in families and has been observed in individuals affected with this condition (PMID: 8528244, 22373669, 22456477, 10376919). This variant is also known as G60R in the literature. ClinVar contains an entry for this variant (Variation ID: 3114). This variant is not present in population databases (ExAC no frequency). This sequence change replaces glycine with arginine at codon 189 of the KCNQ1 protein (p.Gly189Arg). The glycine residue is highly conserved and there is a moderate physicochemical difference between glycine and arginine. -
Congenital long QT syndrome Other:1
not provided, no classification providedliterature onlyCardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust-This variant has been reported as associated with Long QT syndrome in the following publications (PMID:8528244;PMID:10220144;PMID:17470695;PMID:10220144). 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
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.55
D
BayesDel_noAF
Pathogenic
0.55
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.99
.;D;.
Eigen
Pathogenic
0.75
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;D;D
M_CAP
Pathogenic
0.80
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.2
.;M;.
PrimateAI
Uncertain
0.78
T
PROVEAN
Pathogenic
-7.5
D;D;D
REVEL
Pathogenic
0.97
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
1.0
.;D;.
Vest4
0.94, 0.91
MutPred
0.89
.;Loss of methylation at R190 (P = 0.0454);.;
MVP
0.97
MPC
1.3
ClinPred
1.0
D
GERP RS
4.4
Varity_R
0.93
gMVP
0.99

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: rs104894252; hg19: chr11-2591945; COSMIC: COSV50133835; API