rs199473011

Positions:

chr7-150947728-C-T

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 1P and 5B. PP5BP4BS2

The NM_000238.4(KCNH2):c.2843G>A(p.Arg948His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000224 in 1,564,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000022 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3U:8O:1

Conservation

PhyloP100: -0.504

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:

KCNH2 (HGNC:):

KCNH2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

PP5

Variant 7-150947728-C-T is Pathogenic according to our data. Variant chr7-150947728-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 67443.We mark this variant Likely_pathogenic, oryginal submissions are: {Uncertain_significance=8, not_provided=1, Pathogenic=1, Likely_pathogenic=2}.

BP4

Computational evidence support a benign effect (MetaRNN=0.13096884). . Strength limited to SUPPORTING due to the PP5.

BS2

High AC in GnomAdExome4 at 31 AD,Digenic gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNH2	NM_000238.4 linkuse as main transcript	c.2843G>A	p.Arg948His	missense_variant	12/15	ENST00000262186.10	NP_000229.1	Q12809-1Q15BH2A0A090N8Q0

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
KCNH2	ENST00000262186.10 linkuse as main transcript	c.2843G>A	p.Arg948His	missense_variant	12/15	1	NM_000238.4	ENSP00000262186.5	Q12809-1
KCNH2	ENST00000330883.9 linkuse as main transcript	c.1823G>A	p.Arg608His	missense_variant	8/11	1		ENSP00000328531.4	Q12809-2
KCNH2	ENST00000684241.1 linkuse as main transcript	n.3676G>A		non_coding_transcript_exon_variant	10/13

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152150

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:

0.000193

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:

0.0000362

AC:

AN:

165946

Hom.:

AF XY:

0.0000330

AC XY:

AN XY:

90998

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000151

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:

0.0000147

Gnomad OTH exome

AF:

0.000218

GnomAD4 exome

AF:

0.0000219

AC:

AN:

1412738

Hom.:

Cov.:

AF XY:

0.0000243

AC XY:

AN XY:

699240

show subpopulations

Gnomad4 AFR exome

AF:

0.0000307

Gnomad4 AMR exome

AF:

0.000183

Gnomad4 ASJ exome

AF:

0.0000394

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000123

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000193

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152150

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74328

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.000196

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000193

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000189

ExAC

AF:

0.0000347

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3Uncertain:8Other:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Long QT syndrome 2

Pathogenic:2Uncertain:1

Likely pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München	Dec 09, 2017	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Lifecell International Pvt. Ltd	-	A Heterozygous Missense variant c.2843G>A in Exon 12 of the KCNH2 gene that results in the amino acid substitution p.Arg948His was identified. The observed variant has a maximum allele frequency of 0.00004/0.00006% in gnomAD exomes and genomes, respectively. The severity of the impact of this variant on the protein is medium, based on the effect of the protein and REVEL score . Rare Exome Variant Ensemble Learner (REVEL) is an ensembl method for predicting the pathogenicity of missense variants based on a combination of scores from 13 individual tools: MutPred, FATHMM v2.3, VEST 3.0, PolyPhen- 2, SIFT, PROVEAN, MutationAssessor, MutationTaster, LRT, GERP++, SiPhy, phyloP, and phastCons. The REVEL score for an individual missense variant can range from 0 to 1, with higher scores reflecting greater likelihood that the variant is disease-causing. ClinVar has also classified this variant as (Pathogenic/Likely pathogenic/Uncertain significance) Conflicting Interpretations [Variation ID: 67443]. The observed variation has been previously reported in patients affected with long QT syndrome (Itoh H et.al., 2016). For these reasons, this variant has been classified as Likely Pathogenic. -
Uncertain significance, criteria provided, single submitter	clinical testing	Mendelics	May 28, 2019	- -

not provided

Pathogenic:1Uncertain:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Oct 18, 2011	The Arg948His mutation in the KCNH2 gene has been published previously in a single individual from a cohort of Japanese patients with LQTS, and was not detected in 400 control alleles from the same population. Other amino acid substitutions affecting the same codon (Arg948Ser, Arg948Cys) and nearby codons (Ser937Asn, Leu955Val) have also been reported in association with LQTS, further supporting the functional importance of this position and this region of the protein. In addition, Arg948His was not detected in 308 control alleles from individuals of various ethnic backgrounds tested at GeneDx, indicating it is not a common benign variant in these populations. In summary, the presence of Arg948His in the KCNH2 gene is consistent with a diagnosis of LQTS. The variant is found in LQT panel(s). -
Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Sep 01, 2023	KCNH2: PS4:Moderate, PP2 -
Uncertain significance, criteria provided, single submitter	clinical testing	Revvity Omics, Revvity	Sep 13, 2022	- -

Long QT syndrome

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	Aug 30, 2024	This missense variant replaces arginine with histidine at codon 948 of the KCNH2 protein. Computational prediction tools and conservation analyses are inconclusive regarding the impact of this variant on protein structure and function. Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been performed for this variant. This variant has been reported in individuals affected with long QT syndrome (PMID: 20541041, 26669661) and in an individual with prolonged QTc interval (Pottinger et. al, 2019). This variant has also been identified in 8/197252 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 submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 06, 2024	This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 948 of the KCNH2 protein (p.Arg948His). This variant is present in population databases (rs199473011, gnomAD 0.02%). This missense change has been observed in individual(s) with prolonged QT (PMID: 20541041, 32009526, 34319147). ClinVar contains an entry for this variant (Variation ID: 67443). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". 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. -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

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

Mar 18, 2021

Variant summary: KCNH2 c.2843G>A (p.Arg948His) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 3.6e-05 in 165946 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.2843G>A has been reported in the literature in individuals/families affected with Long QT Syndrome (e.g. Itoh_2010, Itoh_2016, Pottinger_2020), without strong evidence for causality. These reports do not provide unequivocal conclusions about association of the variant with Long QT Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Three ClinVar submitters (evaluation after 2014) cite the variant as uncertain significance and one ClinVar submitter (evaluation after 2014) cites it as likely pathogenic. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 02, 2021

The c.2843G>A (p.R948H) alteration is located in exon 12 (coding exon 12) of the KCNH2 gene. This alteration results from a G to A substitution at nucleotide position 2843, causing the arginine (R) at amino acid position 948 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

Uncertain significance, criteria provided, single submitter

clinical testing

Color Diagnostics, LLC DBA Color Health

Dec 15, 2023

This missense variant replaces arginine with histidine at codon 948 of the KCNH2 protein. Computational prediction tools indicate that this variant's impact on protein structure and function is inconclusive. To our knowledge, functional studies have not been reported for this variant. This variant has been reported in five individuals affected with long QT syndrome (PMID: 20541041, 26669661, 34319147, ClinVar SCV000680268.1) and in an individual with prolonged QTc interval (PMID: 32009526). This variant has been identified in 8/197252 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. -

Congenital long QT syndrome

Other:1

not provided, no classification provided

literature only

Cardiovascular Biomedical Research Unit, Royal Brompton & Harefield NHS Foundation Trust

This variant has been reported as associated with Long QT syndrome in the following publications (PMID:20541041). 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

Benign

0.068

BayesDel_addAF

Uncertain

0.026

BayesDel_noAF

Uncertain

0.050

CADD

Benign

DANN

Benign

0.95

DEOGEN2

Benign

0.32

.;T

Eigen

Benign

-0.63

Eigen_PC

Benign

-0.49

FATHMM_MKL

Benign

0.48

LIST_S2

Benign

0.75

T;T

M_CAP

Uncertain

0.25

MetaRNN

Benign

0.13

T;T

MetaSVM

Uncertain

0.056

MutationAssessor

Benign

0.55

.;N

PrimateAI

Uncertain

0.55

PROVEAN

Benign

-0.59

N;N

REVEL

Uncertain

0.54

Sift

Benign

0.14

T;T

Sift4G

Benign

0.31

T;T

Polyphen

0.0

B;B

Vest4

0.38

MutPred

0.45

.;Gain of glycosylation at S951 (P = 0.0712);

MVP

0.99

MPC

0.29

ClinPred

0.27

GERP RS

0.38

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.9

Varity_R

0.037

gMVP

0.51

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

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