7-150958263-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2PP2BP4

The NM_000238.4(KCNH2):​c.712G>A​(p.Gly238Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000277 in 1,442,752 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G238C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000023 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

1
5
14

Clinical Significance

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

Conservation

PhyloP100: -1.85

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: Uncertain_significance. The variant received 2 ACMG points.

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.
BP4
Computational evidence support a benign effect (MetaRNN=0.3135606).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.712G>A p.Gly238Ser missense_variant Exon 4 of 15 ENST00000262186.10 NP_000229.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNH2ENST00000262186.10 linkc.712G>A p.Gly238Ser missense_variant Exon 4 of 15 1 NM_000238.4 ENSP00000262186.5

Frequencies

GnomAD3 genomes
AF:
0.00000659
AC:
1
AN:
151812
Hom.:
0
Cov.:
33
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
GnomAD2 exomes
AF:
0.00
AC:
0
AN:
70640
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000232
AC:
3
AN:
1290940
Hom.:
0
Cov.:
32
AF XY:
0.00000157
AC XY:
1
AN XY:
635830
show subpopulations
African (AFR)
AF:
0.0000382
AC:
1
AN:
26208
American (AMR)
AF:
0.00
AC:
0
AN:
23928
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
21940
East Asian (EAS)
AF:
0.00
AC:
0
AN:
27630
South Asian (SAS)
AF:
0.00
AC:
0
AN:
68336
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
32246
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4000
European-Non Finnish (NFE)
AF:
0.00000194
AC:
2
AN:
1033488
Other (OTH)
AF:
0.00
AC:
0
AN:
53164
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00000659
AC:
1
AN:
151812
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74164
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41402
American (AMR)
AF:
0.00
AC:
0
AN:
15236
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10490
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67878
Other (OTH)
AF:
0.00
AC:
0
AN:
2084
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
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:1Other:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:1
Jan 15, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 238 of the KCNH2 protein (p.Gly238Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with long QT syndrome (PMID: 15840476). ClinVar contains an entry for this variant (Variation ID: 67519). 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 serine 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. -

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:15840476). 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
0.087
CardioboostArm
Benign
0.061
BayesDel_addAF
Uncertain
0.15
D
BayesDel_noAF
Uncertain
-0.020
CADD
Benign
3.2
DANN
Benign
0.89
DEOGEN2
Benign
0.31
T;T
Eigen
Benign
-1.5
Eigen_PC
Benign
-1.6
FATHMM_MKL
Benign
0.016
N
LIST_S2
Benign
0.54
T;T
M_CAP
Pathogenic
0.96
D
MetaRNN
Benign
0.31
T;T
MetaSVM
Uncertain
0.18
D
MutationAssessor
Benign
0.69
N;.
PhyloP100
-1.9
PrimateAI
Uncertain
0.79
T
PROVEAN
Benign
0.040
N;.
REVEL
Uncertain
0.56
Sift
Benign
1.0
T;.
Sift4G
Benign
0.84
T;T
Polyphen
0.0
B;.
Vest4
0.17
MutPred
0.69
Gain of glycosylation at G238 (P = 0.0169);.;
MVP
0.97
MPC
1.0
ClinPred
0.030
T
GERP RS
-2.6
Varity_R
0.032
gMVP
0.36
Mutation Taster
=10/90
disease causing

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

Other links and lift over

dbSNP: rs199473501; hg19: chr7-150655351; API