7-150958110-C-T

Variant names:

Variant summary

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

The NM_000238.4(KCNH2):c.865G>A(p.Glu289Lys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000184 in 1,296,770 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00020 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:10O:1

Conservation

PhyloP100: 1.69

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]

KCNH2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

BS2

High AC in GnomAd4 at 14 AD,Digenic gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNH2	NM_000238.4 link	c.865G>A	p.Glu289Lys	missense_variant	Exon 4 of 15	ENST00000262186.10	NP_000229.1	Q12809-1Q15BH2A0A090N8Q0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
KCNH2	ENST00000262186.10 link	c.865G>A	p.Glu289Lys	missense_variant	Exon 4 of 15	1	NM_000238.4	ENSP00000262186.5	Q12809-1
KCNH2	ENST00000532957.5 link	n.1088G>A		non_coding_transcript_exon_variant	Exon 4 of 9	2
KCNH2	ENST00000684241.1 link	n.1698G>A		non_coding_transcript_exon_variant	Exon 2 of 13

Frequencies

GnomAD3 genomes

AF:

0.0000922

AC:

AN:

151874

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000169

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000208

Gnomad FIN

AF:

0.0000946

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000589

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000255

AC:

AN:

3916

Hom.:

AF XY:

0.00

AC XY:

AN XY:

2326

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:

0.000599

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000196

AC:

224

AN:

1144896

Hom.:

Cov.:

AF XY:

0.000179

AC XY:

AN XY:

548150

show subpopulations

Gnomad4 AFR exome

AF:

0.0000865

Gnomad4 AMR exome

AF:

0.000109

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000378

Gnomad4 SAS exome

AF:

0.0000277

Gnomad4 FIN exome

AF:

0.0000388

Gnomad4 NFE exome

AF:

0.000220

Gnomad4 OTH exome

AF:

0.000150

GnomAD4 genome

AF:

0.0000922

AC:

AN:

151874

Hom.:

Cov.:

AF XY:

0.000135

AC XY:

AN XY:

74170

show subpopulations

Gnomad4 AFR

AF:

0.000169

Gnomad4 AMR

AF:

0.0000655

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000208

Gnomad4 FIN

AF:

0.0000946

Gnomad4 NFE

AF:

0.0000589

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.000110

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:10Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Uncertain:4

Breakthrough Genomics, Breakthrough Genomics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: not provided

- -

Feb 26, 2025

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Reported in association with LQTS and sudden infant death syndrome; however, no detailed clinical information was provided (PMID: 19862833, 29544605, 37589201); Published functional studies suggest that this variant does not significantly impact protein expression (PMID: 26958806); In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 28988457, 19862833, 32048431, 35932045, 37937776, 29544605, 37589201, 26958806) -

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Clinical Genetics, Academic Medical Center

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Long QT syndrome

Uncertain:2

Feb 02, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 289 of the KCNH2 protein (p.Glu289Lys). This variant is present in population databases (rs199472880, gnomAD 0.06%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with clinical features of KCNH2-related conditions (PMID: 19862833, 19926013). ClinVar contains an entry for this variant (Variation ID: 67535). 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 tolerated. Experimental studies have shown that this missense change does not substantially affect KCNH2 function (PMID: 26958806). 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. -

May 29, 2017

Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Long QT syndrome 2

Uncertain:1

Jun 25, 2015

Genomic Diagnostic Laboratory, Division of Genomic Diagnostics, Children's Hospital of Philadelphia

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified

Uncertain:1

Sep 23, 2021

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: KCNH2 c.865G>A (p.Glu289Lys) results in a conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00026 in 3916 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.865G>A has been reported in the literature in individuals affected with Arrhythmia (Hedley_2009, Shimizu_2009, Tester_2018). These reports do not provide unequivocal conclusions about association of the variant with Arrhythmia. At least one publication reports experimental evidence and showed no effect of this variant on protein expression (Perry_2016). Six clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Cardiovascular phenotype

Uncertain:1

Jul 28, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.865G>A (p.E289K) alteration is located in exon 4 (coding exon 4) of the KCNH2 gene. This alteration results from a G to A substitution at nucleotide position 865, causing the glutamic acid (E) at amino acid position 289 to be replaced by a lysine (K). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Short QT syndrome type 1;C3150943:Long QT syndrome 2

Uncertain:1

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

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:19862833). 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

0.70

BayesDel_addAF

Pathogenic

0.18

BayesDel_noAF

Pathogenic

0.38

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.40

T;T

Eigen

Benign

-0.078

Eigen_PC

Benign

0.039

FATHMM_MKL

Uncertain

0.85

LIST_S2

Uncertain

0.91

D;D

M_CAP

Pathogenic

0.94

MetaRNN

Uncertain

0.74

D;D

MetaSVM

Pathogenic

0.94

MutationAssessor

Benign

0.73

N;.

PrimateAI

Pathogenic

0.97

PROVEAN

Benign

-1.5

N;.

REVEL

Pathogenic

0.69

Sift

Benign

0.12

T;.

Sift4G

Benign

0.48

T;T

Polyphen

0.37

B;.

Vest4

0.52

MutPred

0.76

Gain of MoRF binding (P = 0.0028);.;

MVP

1.0

MPC

1.2

ClinPred

0.12

GERP RS

3.8

Varity_R

0.23

gMVP

0.74

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