11-2587636-GC-GCC

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_000218.3(KCNQ1):c.1201dup(p.Arg401ProfsTer62) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000806 in 1,613,742 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. A399A) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

KCNQ1
NM_000218.3 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 2.35

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:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PP5

Variant 11-2587636-G-GC is Pathogenic according to our data. Variant chr11-2587636-G-GC is described in ClinVar as [Pathogenic]. Clinvar id is 52972.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ1	NM_000218.3 linkuse as main transcript	c.1201dup	p.Arg401ProfsTer62	frameshift_variant	9/16	ENST00000155840.12

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ1	ENST00000155840.12 linkuse as main transcript	c.1201dup	p.Arg401ProfsTer62	frameshift_variant	9/16	1	NM_000218.3	P1	P51787-1
KCNQ1	ENST00000335475.6 linkuse as main transcript	c.820dup	p.Arg274ProfsTer62	frameshift_variant	9/16	1			P51787-2
KCNQ1	ENST00000496887.7 linkuse as main transcript	c.844dup	p.Arg282ProfsTer62	frameshift_variant	9/16	5
KCNQ1	ENST00000646564.2 linkuse as main transcript	c.661dup	p.Arg221ProfsTer62	frameshift_variant	4/11

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152146

Hom.:

Cov.:

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:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251228

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135824

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000684

AC:

AN:

1461596

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727104

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000188

Gnomad4 NFE exome

AF:

0.00000719

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152146

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74310

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000151

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Jul 01, 2023	KCNQ1: PVS1, PM2, PS4:Supporting -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Mar 22, 2023	Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 22995991, 15840476, 24357532, 17470695, 23631430, 31765965, 34319147, 31737537, 26582918, 24606995, 35647048) -

Long QT syndrome

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Aug 15, 2023	The c.1201dup (p.Arg401Profs62) variant in the exon 9 of KCNQ1 gene, that encodes for potassium voltage-gated channel subfamily Q member 1, creates a premature termination codon that is predicted to lead to absent or truncated protein product. This variant has been identified in several individuals (>10) affected with Long QT syndrome (LQTS) (PMID: 15840476, 17470695, 23631430, 24606995, 24357532, 19862833, 19716085, 31765965). Loss of function variants are known to be pathogenic for KCNQ1 gene (PMID: 26669661, 29532034, 23098067). This variant is found to be rare (1/251228; 0.00000398) in the general population database (gnomAD) and interpreted as pathogenic by several submitters in the ClinVar database (ClinVar ID: 52972). Therefore, the c.1201dup (p.Arg401Profs62) variant in the KCNQ1 gene is classified as pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	May 25, 2023	This sequence change creates a premature translational stop signal (p.Arg401Profs*62) in the KCNQ1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in KCNQ1 are known to be pathogenic (PMID: 9323054, 19862833). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 52972). This premature translational stop signal has been observed in individuals with long QT syndrome (PMID: 15840476, 17470695, 23631430, 24357532). -

Cardiovascular phenotype

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 29, 2022

The c.1201dupC pathogenic mutation, located in coding exon 9 of the KCNQ1 gene, results from a duplication of C at nucleotide position 1201, causing a translational frameshift with a predicted alternate stop codon. This alteration has been reported in multiple individuals with long QT syndrome (Tester DJ et al. Heart Rhythm. 2005;2(5):507-17; Moss AJ et al. Circulation. 2007;115(19):2481-9; Lieve KV et al. Genet Test Mol Biomarkers. 2013;17(7):553-61; Torekov SS et al. Diabetes. 2014;63(4):1315-25). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Cardiac arrhythmia

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Jun 22, 2023

This variant (also known as P400fs*62 in the literature) inserts 1 nucleotide in exon 9 of the KCNQ1 gene, creating a frameshift and premature translation stop signal. This variant is expected to result in an absent or non-functional protein product. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in multiple individuals affected with or suspected of long QT syndrome (PMID: 15840476, 17470695, 23631430, 24357532, 24606995, 31765965). This variant has been identified in 1/251228 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Loss of KCNQ1 function is a known mechanism of disease (clinicalgenome.org). Based on the available evidence, this variant is classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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