7-150952757-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 4P and 4B. PM1PP2PP3BS2

The NM_000238.4(KCNH2):​c.1225G>A​(p.Val409Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000026 in 1,614,144 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. V409E) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

11
7
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7

Conservation

PhyloP100: 7.76

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 0 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 11 uncertain in NM_000238.4
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, 0.777
BS2
High AC in GnomAdExome4 at 40 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.1225G>A p.Val409Met missense_variant Exon 6 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.1225G>A p.Val409Met missense_variant Exon 6 of 15 1 NM_000238.4 ENSP00000262186.5 Q12809-1

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152146
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000196
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:
0.00
GnomAD2 exomes
AF:
0.0000636
AC:
16
AN:
251470
AF XY:
0.0000589
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000318
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000352
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000274
AC:
40
AN:
1461880
Hom.:
0
Cov.:
34
AF XY:
0.0000303
AC XY:
22
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000291
AC:
13
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.000347
AC:
2
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000171
AC:
19
AN:
1112006
Other (OTH)
AF:
0.0000662
AC:
4
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.474
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.0000131
AC:
2
AN:
152264
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74456
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41538
American (AMR)
AF:
0.000131
AC:
2
AN:
15294
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68022
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
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

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:
0.0000394
Hom.:
0
Bravo
AF:
0.0000302
ExAC
AF:
0.0000659
AC:
8
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:2
Jan 06, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 409 of the KCNH2 protein (p.Val409Met). This variant is present in population databases (rs539146547, gnomAD 0.03%), and has an allele count higher than expected for a pathogenic variant. This missense change has been observed in individual(s) with KCNH2-related conditions (PMID: 31696929, 32233023, 37589201). ClinVar contains an entry for this variant (Variation ID: 456884). 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. -

Sep 27, 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 valine with methionine at codon 409 of the KCNH2 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. This variant is found within a highly conserved pore region (a.a. 404-659). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with epilepsy (PMID: 31696929) and in an individual affected with sudden infant death (PMID: 37589201). This variant has been identified in 16/251470 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. -

Long QT syndrome 2 Uncertain:1
Jun 24, 2022
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0103 - Dominant negative and loss of function are known mechanisms of disease in this gene and are associated with long QT syndrome 2 (MIM#613688). Gain of function is also a known mechanism associated with short QT syndrome 1 (MIM#609620) (OMIM, PMID: 10753933; PMID: 21777565). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0112 - The condition associated with this gene has incomplete penetrance (PMID: 20301308). (I) 0200 - Variant is predicted to result in a missense amino acid change from valine to methionine. (I) 0251 - This variant is heterozygous. (I) 0302 - Variant is present in gnomAD (v2) <0.001 for a dominant condition (16 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2) (1 heterozygote, 0 homozygotes). (I) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0601 - Variant is located in the well-established functional S1 transmembrane domain. The S1 transmembrane domain has been shown to play a role in regulating channel activation and deactivation (PMID: 28280240). (SP) 0710 - Other missense variants comparable to the one identified in this case have inconclusive previous evidence for pathogenicity. Alternative missense changes to glutamic acid and leucine have been described as variants of unknown significance in ClinVar and the literature, respectively (PMID: 32383558). (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. This variant is present in ClinVar as a VUS. It has also been reported as a VUS in the literature in a patient with epilepsy and in a patient with Wolff-Parkinson-White syndrome (PMID: 31696929, 32233023). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Wolff-Parkinson-White pattern Uncertain:1
Jul 14, 2017
Lupski Lab, Baylor-Hopkins CMG, Baylor College of Medicine
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:research

This variant was identified in an individual with Wolff-Parkinson-White syndrome -

not provided Uncertain:1
Feb 08, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Identified in association with epilepsy, sudden infant death syndrome (SIDS), and Wolff-Parkinson-White (WPW) syndrome (PMID: 31696929, 37589201, 32233023); also reported as p.(V69M) due to alternate nomenclature; In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 32233023, 31696929, 37589201) -

Short QT syndrome type 1;C3150943:Long QT syndrome 2 Uncertain:1
Aug 02, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiac arrhythmia Uncertain:1
Jan 03, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces valine with methionine at codon 409 of the KCNH2 protein. Computational prediction tools indicate that this variant has a deleterious impact on protein structure and function. This variant is found within a highly conserved pore region (a.a. 404-659). Rare non-truncating variants in this region have been shown to be significantly overrepresented in individuals with long QT syndrome (PMID: 32893267). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with epilepsy (PMID: 31696929) and in an individual affected with sudden infant death (PMID: 37589201). This variant has been identified in 16/251470 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
0.29
CardioboostArm
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.25
D
BayesDel_noAF
Pathogenic
0.43
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.92
.;D;D
Eigen
Pathogenic
0.69
Eigen_PC
Pathogenic
0.67
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.92
D;D;D
M_CAP
Pathogenic
0.61
D
MetaRNN
Pathogenic
0.78
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Uncertain
2.4
.;M;.
PhyloP100
7.8
PrimateAI
Pathogenic
0.82
D
PROVEAN
Uncertain
-2.8
D;D;.
REVEL
Pathogenic
0.88
Sift
Uncertain
0.0030
D;D;.
Sift4G
Uncertain
0.019
D;D;T
Polyphen
0.88
P;D;.
Vest4
0.86
MutPred
0.44
.;Gain of sheet (P = 0.0477);.;
MVP
0.98
MPC
2.2
ClinPred
0.73
D
GERP RS
4.8
Varity_R
0.54
gMVP
0.85
Mutation Taster
=34/66
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: rs539146547; hg19: chr7-150649845; API