rs199473465

Variant names:

• chr11-2572943-G-A
• rs199473465
• NM_000218.3:c.878G>A

Your query was ambiguous. Multiple possible variants found:

• chr11-2572943-G-A
• chr11-2572943-G-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM1 PP2 BP4

The NM_000218.3(KCNQ1):​c.878G>A​(p.Arg293His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000123 in 1,461,470 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/23 in silico tools predict a benign 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. R293C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.000012 (0 hom.)
• Consequence: KCNQ1 NM_000218.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5 B:1 O:1
• Conservation: PhyloP100: -0.0700
• Publications: 1 publications found

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

ACMG classification

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

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 18 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.
• BP4: Computational evidence support a benign effect (MetaRNN=0.2719402).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNQ1	NM_000218.3	c.878G>A	p.Arg293His	missense_variant	Exon 6 of 16	ENST00000155840.12	NP_000209.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNQ1	ENST00000155840.12	c.878G>A	p.Arg293His	missense_variant	Exon 6 of 16	1	NM_000218.3	ENSP00000155840.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.0000160 AC: 4 AN: 250276 AF XY: 0.0000147

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: 0.0000177

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000123 AC: 18 AN: 1461470 Hom.: 0 Cov.: 32 AF XY: 0.0000110 AC XY: 8 AN XY: 727048

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000224 AC: 1 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000812 AC: 7 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53050

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000809 AC: 9 AN: 1111978

Other (OTH) AF: 0.0000166 AC: 1 AN: 60390

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

Asia WGS AF: 0.000289 AC: 1 AN: 3478

EpiCase AF: 0.000109

EpiControl AF: 0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5 Benign:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Long QT syndrome Uncertain:2

Jan 02, 2025

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 293 of the KCNQ1 protein (p.Arg293His). This variant is present in population databases (rs199473465, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with KCNQ1-related conditions. ClinVar contains an entry for this variant (Variation ID: 67118). An algorithm developed to predict the effect of missense changes on protein structure and function outputs the following: PolyPhen-2: "Benign". The histidine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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. -

Dec 01, 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 arginine with histidine at codon 293 of the KCNQ1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an unaffected control individual in a long QT syndrome case-control study (PMID:19841300). This variant has been identified in 4/250276 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. -

Long QT syndrome 1 Uncertain:1

Apr 15, 2020

Center For Human Genetics And Laboratory Diagnostics, Dr. Klein, Dr. Rost And Colleagues

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Cardiovascular phenotype Uncertain:1

Jan 12, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.878G>A (p.R293H) alteration is located in exon 6 (coding exon 6) of the KCNQ1 gene. This alteration results from a G to A substitution at nucleotide position 878, causing the arginine (R) at amino acid position 293 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

May 20, 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 293 of the KCNQ1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an unaffected control individual in a long QT syndrome case-control study (PMID:19841300). This variant has been identified in 4/250276 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. -

not specified Benign:1

Aug 19, 2011

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

not provided 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 in the following publications (PMID:19841300). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.066
CardioboostArm	Benign	0.000032
BayesDel_addAF	Benign	0.0014	T
BayesDel_noAF	Uncertain	-0.050
CADD	Benign	12
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.87	D;.
Eigen	Benign	-1.0
Eigen_PC	Benign	-1.2
FATHMM_MKL	Benign	0.019	N
LIST_S2	Benign	0.68	T;T
M_CAP	Uncertain	0.28	D
MetaRNN	Benign	0.27	T;T
MetaSVM	Uncertain	0.48	D
MutationAssessor	Benign	0.66	N;.
PhyloP100		-0.070
PrimateAI	Benign	0.30	T
PROVEAN	Benign	-2.3	N;N
REVEL	Uncertain	0.52
Sift	Uncertain	0.0070	D;D
Sift4G	Uncertain	0.029	D;D
Polyphen		0.83	P;P
Vest4		0.30
MutPred		0.48		Gain of disorder (P = 0.1129);.;
MVP		0.80
MPC		0.47
ClinPred		0.091	T
GERP RS		-3.1
Varity_R		0.19
gMVP		0.83
Mutation Taster		=71/29	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

Other links and lift over

dbSNP: rs199473465; hg19: chr11-2594173; COSMIC: COSV50105016; COSMIC: COSV50105016;