7-150958407-C-T

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 1P and 7B. PP2BP4_ModerateBP6BS2

The NM_000238.4(KCNH2):​c.568G>A​(p.Ala190Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000131 in 1,428,080 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/23 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A190V) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00072 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000062 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

1
3
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:4O:1

Conservation

PhyloP100: 1.90

Publications

5 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_benign. The variant received -6 ACMG points.

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=0.1471112).
BP6
Variant 7-150958407-C-T is Benign according to our data. Variant chr7-150958407-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 67512.
BS2
High AC in GnomAd4 at 108 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.568G>A p.Ala190Thr missense_variant Exon 4 of 15 ENST00000262186.10 NP_000229.1 Q12809-1Q15BH2A0A090N8Q0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNH2ENST00000262186.10 linkc.568G>A p.Ala190Thr missense_variant Exon 4 of 15 1 NM_000238.4 ENSP00000262186.5 Q12809-1

Frequencies

GnomAD3 genomes
AF:
0.000716
AC:
108
AN:
150782
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00253
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000263
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:
0.000482
GnomAD2 exomes
AF:
0.000144
AC:
7
AN:
48596
AF XY:
0.000105
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000741
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:
0.000678
GnomAD4 exome
AF:
0.0000619
AC:
79
AN:
1277188
Hom.:
0
Cov.:
32
AF XY:
0.0000462
AC XY:
29
AN XY:
628120
show subpopulations
African (AFR)
AF:
0.00253
AC:
63
AN:
24858
American (AMR)
AF:
0.000594
AC:
11
AN:
18516
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
20126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
27840
South Asian (SAS)
AF:
0.00
AC:
0
AN:
64454
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
32098
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
3998
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1032616
Other (OTH)
AF:
0.0000949
AC:
5
AN:
52682
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.518
Heterozygous variant carriers
0
5
10
14
19
24
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:
0.000716
AC:
108
AN:
150892
Hom.:
0
Cov.:
33
AF XY:
0.000664
AC XY:
49
AN XY:
73766
show subpopulations
African (AFR)
AF:
0.00253
AC:
103
AN:
40760
American (AMR)
AF:
0.000263
AC:
4
AN:
15224
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3460
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5064
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4798
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10480
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
290
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67808
Other (OTH)
AF:
0.000477
AC:
1
AN:
2098
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
5
10
16
21
26
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.000498
Hom.:
0
Bravo
AF:
0.000865
ExAC
AF:
0.0000458
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:4Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:2
Mar 03, 2020
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 06, 2018
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: KCNH2 c.568G>A (p.Ala190Thr) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant was observed with an allele frequency of 0.00085 in 31934 control chromosomes (gnomAD and publication controls). The observed variant frequency within African control individuals in the gnomAD database is approximately 28 fold of the estimated maximal expected allele frequency for a pathogenic variant in KCNH2 causing Arrhythmia phenotype (0.0001), strongly suggesting that the variant is a benign polymorphism found primarily in populations of African origin. The variant, c.568G>A, has been reported in the literature in individuals affected with Arrhythmia. These report(s) do not provide unequivocal conclusions about association of the variant with Arrhythmia. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. A ClinVar submission from a clinical diagnostic laboratory (evaluation after 2014) cites variant as "uncertain significance." Based on the evidence outlined above, the variant was classified as benign. -

Long QT syndrome Uncertain:1
Feb 04, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 190 of the KCNH2 protein (p.Ala190Thr). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This missense change has been observed in individual(s) with sudden infant death syndrome (PMID: 29752375). ClinVar contains an entry for this variant (Variation ID: 67512). 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. 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. -

Short QT syndrome type 1;C3150943:Long QT syndrome 2 Uncertain:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiovascular phenotype Benign:1
Aug 25, 2020
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

KCNH2-related disorder Benign:1
Aug 07, 2019
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

not provided 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 in the following publications (PMID:14661677;PMID:19841300). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.072
CardioboostArm
Benign
0.000026
BayesDel_addAF
Benign
-0.23
T
BayesDel_noAF
Benign
-0.11
CADD
Benign
15
DANN
Benign
0.96
DEOGEN2
Benign
0.33
T
Eigen
Benign
-0.82
Eigen_PC
Benign
-0.77
FATHMM_MKL
Benign
0.53
D
LIST_S2
Benign
0.78
T
M_CAP
Pathogenic
0.89
D
MetaRNN
Benign
0.15
T
MetaSVM
Uncertain
0.67
D
MutationAssessor
Benign
1.1
L
PhyloP100
1.9
PrimateAI
Uncertain
0.78
T
PROVEAN
Benign
-0.080
N
REVEL
Uncertain
0.41
Sift
Benign
0.53
T
Sift4G
Benign
0.45
T
Polyphen
0.41
B
Vest4
0.19
MVP
0.86
MPC
0.99
ClinPred
0.044
T
GERP RS
2.1
Varity_R
0.028
gMVP
0.28
Mutation Taster
=84/16
polymorphism

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: rs150817714; hg19: chr7-150655495; API