rs199472710

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_000218.3(KCNQ1):​c.704T>A​(p.Ile235Asn) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I235L) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)

Consequence

KCNQ1
NM_000218.3 missense

Scores

16
3
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:2O:1

Conservation

PhyloP100: 5.80

Publications

10 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: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 21 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 12 uncertain 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 chr11-2572032-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 3641656.Status of the report is criteria_provided_single_submitter, 1 stars.
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, 0.984
PP5
Variant 11-2572033-T-A is Pathogenic according to our data. Variant chr11-2572033-T-A is described in ClinVar as Pathogenic. ClinVar VariationId is 53088.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ1NM_000218.3 linkc.704T>A p.Ile235Asn missense_variant Exon 5 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.704T>A p.Ile235Asn missense_variant Exon 5 of 16 1 NM_000218.3 ENSP00000155840.2 P51787-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
Cov.:
31
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:2Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome Pathogenic:1
Feb 18, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects KCNQ1 function (PMID: 19590188, 24269949). 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. ClinVar contains an entry for this variant (Variation ID: 53088). This missense change has been observed in individuals with long QT syndrome (PMID: 18452873, 22949429, 24269949). It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces isoleucine, which is neutral and non-polar, with asparagine, which is neutral and polar, at codon 235 of the KCNQ1 protein (p.Ile235Asn). -

Cardiac arrhythmia Pathogenic:1
Aug 31, 2021
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: KCNQ1 c.704T>A (p.Ile235Asn) results in a non-conservative amino acid change located in the Ion transport domain (IPR005821; voltage sensor transmembrane domain S4 in Henrion_2009) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant was absent in 248876 control chromosomes (gnomAD). c.704T>A has been reported in the literature in multiple individuals affected with Long QT Syndrome as well as ten individuals with concealed LQT1 in one family (Choi_2004, Johnson_2008, Bartos_2013). These data indicate that the variant is very likely to be associated with disease. Functional studies report experimental evidence evaluating an impact on protein function and this variant effect results in reducing KCNQ1 channel currents in a dominant-negative manner and impaired Protein Kinase A response of slow delayed rectifier potassium channels. One ClinVar submitter (evaluation after 2014) cites the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -

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:15466642;PMID:15840476;PMID:19590188;PMID:19716085;PMID:19841300). 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
CardioboostArm
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.39
D
BayesDel_noAF
Pathogenic
0.32
CADD
Pathogenic
27
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.99
.;D;.
Eigen
Uncertain
0.53
Eigen_PC
Uncertain
0.44
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;D;D
M_CAP
Pathogenic
0.93
D
MetaRNN
Pathogenic
0.98
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.1
.;M;.
PhyloP100
5.8
PrimateAI
Pathogenic
0.91
D
PROVEAN
Pathogenic
-6.7
D;D;D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0
D;D;D
Polyphen
0.98, 0.68
.;D;P
Vest4
0.98
MutPred
0.89
.;Gain of methylation at R231 (P = 0.0409);.;
MVP
1.0
MPC
1.4
ClinPred
1.0
D
GERP RS
4.2
Varity_R
0.97
gMVP
1.0
Mutation Taster
=1/99
disease causing (ClinVar)

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: rs199472710; hg19: chr11-2593263; API