chr7-150945397-G-T

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 1P and 6B. PP2BP4BS1_SupportingBS2

The NM_000238.4(KCNH2):​c.3448C>A​(p.Leu1150Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000221 in 1,587,108 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 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

2
7
11

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:6B:1

Conservation

PhyloP100: 2.23

Publications

1 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 -5 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=0.3292657).
BS1
Variant frequency is greater than expected in population mid. GnomAdExome4 allele frequency = 0.0000237 (34/1434894) while in subpopulation MID AF = 0.00459 (25/5448). AF 95% confidence interval is 0.00319. There are 0 homozygotes in GnomAdExome4. There are 21 alleles in the male GnomAdExome4 subpopulation. Median coverage is 31. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAdExome4 at 34 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.3448C>A p.Leu1150Met missense_variant Exon 15 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.3448C>A p.Leu1150Met missense_variant Exon 15 of 15 1 NM_000238.4 ENSP00000262186.5 Q12809-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152214
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:
0.0000551
AC:
11
AN:
199644
AF XY:
0.0000925
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.000111
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000353
Gnomad OTH exome
AF:
0.00117
GnomAD4 exome
AF:
0.0000237
AC:
34
AN:
1434894
Hom.:
0
Cov.:
31
AF XY:
0.0000295
AC XY:
21
AN XY:
711284
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33004
American (AMR)
AF:
0.00
AC:
0
AN:
41390
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25596
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38394
South Asian (SAS)
AF:
0.0000365
AC:
3
AN:
82232
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50476
Middle Eastern (MID)
AF:
0.00459
AC:
25
AN:
5448
European-Non Finnish (NFE)
AF:
0.00000273
AC:
3
AN:
1099088
Other (OTH)
AF:
0.0000506
AC:
3
AN:
59266
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.484
Heterozygous variant carriers
0
3
5
8
10
13
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:
152214
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41460
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4838
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
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
Alfa
AF:
0.000528
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.0000750
AC:
9

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:6Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:2
Dec 22, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces leucine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 1150 of the KCNH2 protein (p.Leu1150Met). This variant is present in population databases (rs754883792, gnomAD 0.005%). This variant has not been reported in the literature in individuals affected with KCNH2-related conditions. ClinVar contains an entry for this variant (Variation ID: 456931). 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 disruptive. 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. -

Aug 13, 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 leucine with methionine at codon 1150 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 not been reported in individuals affected with cardiovascular disorders in the literature. This variant has been identified in 11/199644 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. -

not provided Uncertain:1Benign:1
Jan 01, 2025
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

KCNH2: BS1 -

Sep 09, 2019
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified in one stillborn male without congenital malformations or chromosomal abnormalities in published literature (Sahlin et al., 2019), although at least one other variant in a different gene was also identified and no segregation studies were described; Reported in ClinVar as a variant of uncertain significance but additional evidence is not available (ClinVar Variant ID 456931; Landrum et al., 2016); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 30615648) -

Cardiovascular phenotype Uncertain:1
Jun 17, 2021
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.L1150M variant (also known as c.3448C>A), located in coding exon 15 of the KCNH2 gene, results from a C to A substitution at nucleotide position 3448. The leucine at codon 1150 is replaced by methionine, an amino acid with highly similar properties, and is located in the cytoplasmic C-terminal region. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

KCNH2-related disorder Uncertain:1
Mar 14, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The KCNH2 c.3448C>A variant is predicted to result in the amino acid substitution p.Leu1150Met. To our knowledge, this variant has not been reported in the literature. This variant is reported in 0.011% of alleles in individuals of Ashkenazi Jewish descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Cardiac arrhythmia Uncertain:1
Jul 24, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces leucine with methionine at codon 1150 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 a fetus affected with stillbirth (PMID: 30615648). This variant has been identified in 11/199644 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
CardioboostArm
Benign
0.021
BayesDel_addAF
Uncertain
0.092
D
BayesDel_noAF
Uncertain
0.030
CADD
Benign
20
DANN
Uncertain
1.0
DEOGEN2
Benign
0.40
.;T
Eigen
Benign
0.15
Eigen_PC
Benign
0.15
FATHMM_MKL
Uncertain
0.87
D
LIST_S2
Benign
0.76
T;T
M_CAP
Pathogenic
0.29
D
MetaRNN
Benign
0.33
T;T
MetaSVM
Pathogenic
0.90
D
MutationAssessor
Benign
1.5
.;L
PhyloP100
2.2
PrimateAI
Uncertain
0.70
T
PROVEAN
Benign
-0.61
N;N
REVEL
Uncertain
0.55
Sift
Uncertain
0.024
D;D
Sift4G
Benign
0.15
T;T
Polyphen
0.98
D;D
Vest4
0.31
MutPred
0.19
.;Gain of MoRF binding (P = 0.1565);
MVP
0.66
MPC
0.66
ClinPred
0.14
T
GERP RS
3.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.11
gMVP
0.15
Mutation Taster
=61/39
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: rs754883792; hg19: chr7-150642485; API