rs199472841

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1PM2PP2PP3_Strong

The NM_000238.4(KCNH2):​c.150G>T​(p.Glu50Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,611,780 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. E50K) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 34)
Exomes 𝑓: 6.9e-7 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

5
5
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3O:1

Conservation

PhyloP100: 0.229

Publications

6 publications found
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 Gene-Disease associations (from GenCC):
  • long QT syndrome
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • long QT syndrome 2
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, G2P
  • short QT syndrome
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
  • short QT syndrome type 1
    Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • Brugada syndrome
    Inheritance: AD Classification: MODERATE, NO_KNOWN Submitted by: ClinGen, Genomics England PanelApp

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

PM1
In a hotspot region, there are 21 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 23 uncertain in NM_000238.4
PM2
Very rare variant in population databases, with high coverage;
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 158 curated pathogenic missense variants (we use a threshold of 10). The gene has 38 curated benign missense variants. Gene score misZ: 3.3724 (above the threshold of 3.09). Trascript score misZ: 2.4846 (below the threshold of 3.09). GenCC associations: The gene is linked to long QT syndrome 2, Brugada syndrome, short QT syndrome type 1, short QT syndrome, long QT syndrome.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.976

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.150G>T p.Glu50Asp missense_variant Exon 2 of 15 ENST00000262186.10 NP_000229.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNH2ENST00000262186.10 linkc.150G>T p.Glu50Asp missense_variant Exon 2 of 15 1 NM_000238.4 ENSP00000262186.5
KCNH2ENST00000713710.1 linkc.150G>T p.Glu50Asp missense_variant Exon 2 of 15 ENSP00000519013.1
KCNH2ENST00000532957.5 linkn.373G>T non_coding_transcript_exon_variant Exon 2 of 9 2
KCNH2ENST00000713700.1 linkn.108G>T non_coding_transcript_exon_variant Exon 2 of 9

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152250
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
6.85e-7
AC:
1
AN:
1459530
Hom.:
0
Cov.:
34
AF XY:
0.00000138
AC XY:
1
AN XY:
725996
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33416
American (AMR)
AF:
0.00
AC:
0
AN:
44570
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26074
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39632
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86082
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52560
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5704
European-Non Finnish (NFE)
AF:
9.00e-7
AC:
1
AN:
1111220
Other (OTH)
AF:
0.00
AC:
0
AN:
60272
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152250
Hom.:
0
Cov.:
34
AF XY:
0.00
AC XY:
0
AN XY:
74374
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41472
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:2
May 02, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

ClinVar contains an entry for this variant (Variation ID: 67211). 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. 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. This missense change has been observed in individual(s) with KCNH2-related conditions (PMID: 19340359). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamic acid, which is acidic and polar, with aspartic acid, which is acidic and polar, at codon 50 of the KCNH2 protein (p.Glu50Asp). -

Jul 29, 2024
All of Us Research Program, National Institutes of Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces glutamic acid with aspartic acid at codon 50 of the KCNH2 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in at least 1 individual affected with short QT syndrome (PMID: 19340359) and 1 individual with suspected short QT syndrome (doi/10.1161/circ.124.suppl_21.A12845). This variant has not been identified 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. -

Cardiovascular phenotype Uncertain:1
Jun 06, 2016
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.150G>T (p.E50D) alteration is located in exon 2 (coding exon 2) of the KCNH2 gene. This alteration results from a G to T substitution at nucleotide position 150, causing the glutamic acid (E) at amino acid position 50 to be replaced by an aspartic acid (D). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Short 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 Short QT syndrome in the following publications (PMID:19340359). 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
0.10
CardioboostArm
Benign
0.0014
BayesDel_addAF
Pathogenic
0.27
D
BayesDel_noAF
Pathogenic
0.15
CADD
Benign
21
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.71
D
Eigen
Benign
-0.39
Eigen_PC
Benign
-0.27
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.81
T
M_CAP
Pathogenic
0.84
D
MetaRNN
Pathogenic
0.98
D
MetaSVM
Pathogenic
0.98
D
MutationAssessor
Benign
1.3
L
PhyloP100
0.23
PrimateAI
Uncertain
0.75
T
PROVEAN
Benign
-1.4
N
REVEL
Uncertain
0.62
Sift
Benign
0.037
D
Sift4G
Benign
0.097
T
Polyphen
0.0
B
Vest4
0.79
MutPred
0.89
Gain of helix (P = 0.2684);
MVP
1.0
MPC
1.0
ClinPred
0.42
T
GERP RS
2.6
Varity_R
0.35
gMVP
0.86
Mutation Taster
=17/83
disease causing

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

Other links and lift over

dbSNP: rs199472841; hg19: chr7-150671956; API