7-150952757-C-T

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PM1PP3BS2

The NM_000238.4(KCNH2):c.1225G>A(p.Val409Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000026 in 1,614,144 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 7.76

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 -1 ACMG points.

PM1

In a transmembrane_region Helical; Name=Segment S1 (size 20) in uniprot entity KCNH2_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_000238.4

PP3

MetaRNN computational evidence supports a deleterious effect, 0.777

BS2

High AC in GnomAdExome4 at 40 AD,Digenic gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNH2	NM_000238.4 link	c.1225G>A	p.Val409Met	missense_variant	Exon 6 of 15	ENST00000262186.10	NP_000229.1	Q12809-1Q15BH2A0A090N8Q0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNH2	ENST00000262186.10 link	c.1225G>A	p.Val409Met	missense_variant	Exon 6 of 15	1	NM_000238.4	ENSP00000262186.5		Q12809-1

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:

0.000196

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000636

AC:

AN:

251470

Hom.:

AF XY:

0.0000589

AC XY:

AN XY:

135910

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000318

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:

0.0000352

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000274

AC:

AN:

1461880

Hom.:

Cov.:

AF XY:

0.0000303

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000291

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000171

Gnomad4 OTH exome

AF:

0.0000662

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152264

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74456

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000277

Hom.:

Bravo

AF:

0.0000302

ExAC

AF:

0.0000659

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Long QT syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 06, 2025	This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 409 of the KCNH2 protein (p.Val409Met). This variant is present in population databases (rs539146547, gnomAD 0.03%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with KCNH2-related conditions (PMID: 31696929, 32233023, 37589201). ClinVar contains an entry for this variant (Variation ID: 456884). 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Sep 27, 2024	This missense variant replaces valine with methionine at codon 409 of the KCNH2 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. This variant is found within a highly conserved pore region (a.a. 404-659). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with epilepsy (PMID: 31696929) and in an individual affected with sudden infant death (PMID: 37589201). This variant has been identified in 16/251470 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. -

Wolff-Parkinson-White pattern

Uncertain:1

Uncertain significance, no assertion criteria provided

research

Lupski Lab, Baylor-Hopkins CMG, Baylor College of Medicine

Jul 14, 2017

This variant was identified in an individual with Wolff-Parkinson-White syndrome -

Long QT syndrome 2

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Jun 24, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0103 - Dominant negative and loss of function are known mechanisms of disease in this gene and are associated with long QT syndrome 2 (MIM#613688). Gain of function is also a known mechanism associated with short QT syndrome 1 (MIM#609620) (OMIM, PMID: 10753933; PMID: 21777565). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0112 - The condition associated with this gene has incomplete penetrance (PMID: 20301308). (I) 0200 - Variant is predicted to result in a missense amino acid change from valine to methionine. (I) 0251 - This variant is heterozygous. (I) 0302 - Variant is present in gnomAD (v2) <0.001 for a dominant condition (16 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2) (1 heterozygote, 0 homozygotes). (I) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0601 - Variant is located in the well-established functional S1 transmembrane domain. The S1 transmembrane domain has been shown to play a role in regulating channel activation and deactivation (PMID: 28280240). (SP) 0710 - Other missense variants comparable to the one identified in this case have inconclusive previous evidence for pathogenicity. Alternative missense changes to glutamic acid and leucine have been described as variants of unknown significance in ClinVar and the literature, respectively (PMID: 32383558). (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. This variant is present in ClinVar as a VUS. It has also been reported as a VUS in the literature in a patient with epilepsy and in a patient with Wolff-Parkinson-White syndrome (PMID: 31696929, 32233023). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Feb 08, 2024

Identified in association with epilepsy, sudden infant death syndrome (SIDS), and Wolff-Parkinson-White (WPW) syndrome (PMID: 31696929, 37589201, 32233023); also reported as p.(V69M) due to alternate nomenclature; In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 32233023, 31696929, 37589201) -

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

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Aug 02, 2021

- -

Cardiac arrhythmia

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Jan 03, 2024

This missense variant replaces valine with methionine at codon 409 of the KCNH2 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. This variant is found within a highly conserved pore region (a.a. 404-659). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with epilepsy (PMID: 31696929) and in an individual affected with sudden infant death (PMID: 37589201). This variant has been identified in 16/251470 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

Benign

0.29

BayesDel_addAF

Pathogenic

0.25

BayesDel_noAF

Pathogenic

0.43

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.92

.;D;D

Eigen

Pathogenic

0.69

Eigen_PC

Pathogenic

0.67

FATHMM_MKL

Uncertain

0.94

LIST_S2

Uncertain

0.92

D;D;D

M_CAP

Pathogenic

0.61

MetaRNN

Pathogenic

0.78

D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.4

.;M;.

PrimateAI

Pathogenic

0.82

PROVEAN

Uncertain

-2.8

D;D;.

REVEL

Pathogenic

0.88

Sift

Uncertain

0.0030

D;D;.

Sift4G

Uncertain

0.019

D;D;T

Polyphen

0.88

P;D;.

Vest4

0.86

MutPred

0.44

.;Gain of sheet (P = 0.0477);.;

MVP

0.98

MPC

2.2

ClinPred

0.73

GERP RS

4.8

Varity_R

0.54

gMVP

0.85

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