rs199473003

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1PM2PM5PP3_Strong

The NM_000238.4(KCNH2):c.2503C>T(p.Arg835Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,190 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R835Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Consequence

KCNH2
NM_000238.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1O:1

Conservation

PhyloP100: 3.00

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 Pathogenic. Variant got 10 ACMG points.

PM1

In a helix (size 9) in uniprot entity KCNH2_HUMAN there are 5 pathogenic changes around while only 0 benign (100%) in NM_000238.4

PM2

Very rare variant in population databases, with high coverage;

PM5

Other missense variant is known to change same aminoacid residue: Variant chr7-150948944-C-T is described in Lovd as [Likely_pathogenic].

PP3

MetaRNN computational evidence supports a deleterious effect, 0.986

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNH2	NM_000238.4 linkuse as main transcript	c.2503C>T	p.Arg835Trp	missense_variant	10/15	ENST00000262186.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNH2	ENST00000262186.10 linkuse as main transcript	c.2503C>T	p.Arg835Trp	missense_variant	10/15	1	NM_000238.4	P1	Q12809-1
KCNH2	ENST00000330883.9 linkuse as main transcript	c.1483C>T	p.Arg495Trp	missense_variant	6/11	1			Q12809-2
KCNH2	ENST00000684241.1 linkuse as main transcript	n.3336C>T		non_coding_transcript_exon_variant	8/13

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.000288

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

GnomAD4 exome

Cov.:

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74346

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.000288

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:

0.0000712

Hom.:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1Other:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Long QT syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Jun 28, 2023

- -

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:14998624). 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

0.98

CardioboostArm

Pathogenic

0.93

BayesDel_addAF

Pathogenic

0.52

BayesDel_noAF

Pathogenic

0.50

Cadd

Pathogenic

Dann

Uncertain

1.0

Eigen

Benign

-0.056

Eigen_PC

Benign

-0.21

FATHMM_MKL

Uncertain

0.79

LIST_S2

Uncertain

0.92

D;D

M_CAP

Pathogenic

0.79

MetaRNN

Pathogenic

0.99

D;D

MetaSVM

Pathogenic

1.0

MutationTaster

Benign

0.95

D;D;D

PrimateAI

Pathogenic

0.84

PROVEAN

Pathogenic

-7.4

D;D

REVEL

Pathogenic

0.85

Sift

Uncertain

0.0050

D;D

Sift4G

Pathogenic

0.0010

D;D

Polyphen

0.40

B;D

Vest4

0.94

MutPred

0.86

.;Loss of glycosylation at K832 (P = 0.119);

MVP

1.0

MPC

2.2

ClinPred

1.0

GERP RS

2.0

Varity_R

0.48

gMVP

0.97

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