rs780656919

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 0P and 4B. BS2

The ENST00000262186.10(KCNH2):​c.2144C>T​(p.Ala715Val) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.0000103 in 1,461,722 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A715A) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

KCNH2
ENST00000262186.10 missense, splice_region

Scores

8
5
6
Splicing: ADA: 0.8268
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 5.89
Variant links:
Genes affected
KCNH2 (HGNC:6251): (potassium voltage-gated channel subfamily H member 2) This gene encodes a component of a voltage-activated potassium channel found in cardiac muscle, nerve cells, and microglia. Four copies of this protein interact with one copy of the KCNE2 protein to form a functional potassium channel. Mutations in this gene can cause long QT syndrome type 2 (LQT2). Transcript variants encoding distinct isoforms have been identified. [provided by RefSeq, May 2022]

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ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2
High AC in GnomAdExome4 at 15 AD,Digenic gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
KCNH2NM_000238.4 linkuse as main transcriptc.2144C>T p.Ala715Val missense_variant, splice_region_variant 8/15 ENST00000262186.10 NP_000229.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
KCNH2ENST00000262186.10 linkuse as main transcriptc.2144C>T p.Ala715Val missense_variant, splice_region_variant 8/151 NM_000238.4 ENSP00000262186 P1Q12809-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.0000279
AC:
7
AN:
251312
Hom.:
0
AF XY:
0.0000294
AC XY:
4
AN XY:
135860
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000992
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000440
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000103
AC:
15
AN:
1461722
Hom.:
0
Cov.:
33
AF XY:
0.00000963
AC XY:
7
AN XY:
727172
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.000115
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000108
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
33
Alfa
AF:
0.000144
Hom.:
0
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingAll of Us Research Program, National Institutes of HealthJul 20, 2024This missense variant replaces alanine with valine at codon 715 of the KCNH2 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). A functional study showed that this variant had similar expression compared to wild type (PMID: 26958806). This variant has been reported in individuals affected with long QT syndrome. However, those individuals have other long QT syndrome related co-variants (PMID: 23174487). This variant has been identified in 8/282710 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. -
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJul 29, 2023Experimental studies have shown that this missense change does not substantially affect KCNH2 function (PMID: 26958806). This sequence change replaces alanine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 715 of the KCNH2 protein (p.Ala715Val). This variant is present in population databases (rs780656919, gnomAD 0.01%). This missense change has been observed in individual(s) with long QT syndrome (LQTS) (PMID: 23174487). ClinVar contains an entry for this variant (Variation ID: 200413). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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 specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingLaboratory for Molecular Medicine, Mass General Brigham Personalized MedicineMar 31, 2016Variant identified in a genome or exome case(s) and assessed due to predicted null impact of the variant or pathogenic assertions in the literature or databases. Disclaimer: This variant has not undergone full assessment. The following are preliminary notes: No predicted splice impact; 1 paper in HGMD; ExAC: 2/66498 European; ClinVar: 1 VUS -
Cardiovascular phenotype Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsNov 07, 2016The p.A715V variant (also known as c.2144C>T), located in coding exon 8 of the KCNH2 gene, results from a C to T substitution at nucleotide position 2144. The alanine at codon 715 is replaced by valine, an amino acid with similar properties. This alteration was detected in a long QT syndrome (LQTS) cohort; however, the patients harbored multiple LQTS alterations and clinical data was not provided (Mullally J et al. Heart Rhythm. 2013;10:378-82). This variant was previously reported in the SNP database (dbSNP) as rs780656919. Based on data from ExAC, the T allele has an overall frequency of less than 0.01% (1/105914). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Cardiac arrhythmia Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingColor Diagnostics, LLC DBA Color HealthDec 06, 2022This missense variant replaces alanine with valine at codon 715 of the KCNH2 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). A functional study showed that this variant had similar expression compared to wild type (PMID: 26958806). This variant has been reported in individuals affected with long QT syndrome. However, those individuals have other long QT syndrome related co-variants (PMID: 23174487). This variant has been identified in 8/282710 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.72
BayesDel_addAF
Pathogenic
0.38
D
BayesDel_noAF
Pathogenic
0.45
CADD
Pathogenic
34
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.62
.;D;T
Eigen
Uncertain
0.21
Eigen_PC
Benign
0.21
FATHMM_MKL
Uncertain
0.88
D
LIST_S2
Uncertain
0.93
D;D;D
M_CAP
Pathogenic
0.61
D
MetaRNN
Uncertain
0.69
D;D;D
MetaSVM
Pathogenic
0.98
D
MutationAssessor
Benign
1.9
.;L;.
MutationTaster
Benign
1.0
D;D;D;D
PrimateAI
Pathogenic
0.84
D
PROVEAN
Benign
-2.3
N;N;.
REVEL
Pathogenic
0.77
Sift
Benign
0.19
T;T;.
Sift4G
Benign
0.21
T;T;T
Polyphen
0.76
P;P;.
Vest4
0.66
MutPred
0.44
.;Loss of catalytic residue at A715 (P = 0.0772);.;
MVP
0.99
MPC
1.7
ClinPred
0.72
D
GERP RS
4.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.24
gMVP
0.85

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.83
dbscSNV1_RF
Benign
0.50
SpliceAI score (max)
0.12
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: rs780656919; hg19: chr7-150648010; API