rs199473543

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 3P and 4B. PM1PP2BS2

The NM_000238.4(KCNH2):​c.3103C>T​(p.Arg1035Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000323 in 1,548,114 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R1035Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

5
10
5

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7O:1

Conservation

PhyloP100: 1.67

Publications

3 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 -1 ACMG points.

PM1
In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 29 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.
BS2
High AC in GnomAdExome4 at 46 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.3103C>T p.Arg1035Trp missense_variant Exon 13 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.3103C>T p.Arg1035Trp missense_variant Exon 13 of 15 1 NM_000238.4 ENSP00000262186.5 Q12809-1

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152108
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.000478
GnomAD2 exomes
AF:
0.0000275
AC:
4
AN:
145334
AF XY:
0.0000127
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000820
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000182
Gnomad OTH exome
AF:
0.000240
GnomAD4 exome
AF:
0.0000330
AC:
46
AN:
1396006
Hom.:
0
Cov.:
35
AF XY:
0.0000319
AC XY:
22
AN XY:
688622
show subpopulations
African (AFR)
AF:
0.0000630
AC:
2
AN:
31722
American (AMR)
AF:
0.0000561
AC:
2
AN:
35668
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35958
South Asian (SAS)
AF:
0.0000379
AC:
3
AN:
79184
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
46176
Middle Eastern (MID)
AF:
0.000192
AC:
1
AN:
5216
European-Non Finnish (NFE)
AF:
0.0000334
AC:
36
AN:
1079086
Other (OTH)
AF:
0.0000345
AC:
2
AN:
57888
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.473
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
4
8
12
16
20
<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:
0.0000263
AC:
4
AN:
152108
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74306
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41420
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5162
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67994
Other (OTH)
AF:
0.000478
AC:
1
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
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:
0.00
Hom.:
0
Bravo
AF:
0.0000529

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2Other:1
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

May 01, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Reported in a patient with Short QT syndrome and idiopathic ventricular fibrillation (PMID: 28566242); Reported in a healthy control individual in published literature (PMID: 14661677); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 19841300, 22947121, 22581653, 22949429, 14661677, 28566242) -

-
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). -

Long QT syndrome Uncertain:2
May 30, 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 arginine with tryptophan at codon 1035 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 performed for this variant. This variant has been reported in an individual affected with cardiac arrest, idiopathic ventricular fibrillation and short QT syndrome and in this individual's relative suspected of having short QT syndrome (PMID: 28566242, Jimenez-Jaimez et al., 2016). This variant has also been reported in healthy individuals (PMID: 14661677, 19841300, 22949429). This variant has been identified in 5/176612 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. -

Oct 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with tryptophan, which is neutral and slightly polar, at codon 1035 of the KCNH2 protein (p.Arg1035Trp). This variant is present in population databases (rs199473543, gnomAD 0.008%). 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: 67468). 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. -

Cardiovascular phenotype Uncertain:1
Jan 28, 2022
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.3103C>T (p.R1035W) alteration is located in exon 13 (coding exon 13) of the KCNH2 gene. This alteration results from a C to T substitution at nucleotide position 3103, causing the arginine (R) at amino acid position 1035 to be replaced by a tryptophan (W). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Short QT syndrome type 1;C3150943:Long QT syndrome 2 Uncertain:1
Aug 12, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Cardiac arrhythmia Uncertain:1
Apr 23, 2024
Color Diagnostics, LLC DBA Color Health
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This missense variant replaces arginine with tryptophan at codon 1035 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 performed for this variant. This variant has been reported in an individual affected with cardiac arrest, idiopathic ventricular fibrillation and short QT syndrome and in this individual's relative suspected of having short QT syndrome (PMID: 28566242, Jimenez-Jaimez et al., 2016). This variant has also been reported in healthy individuals (PMID: 14661677, 19841300, 22949429). This variant has been identified in 5/176612 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
0.11
CardioboostArm
Uncertain
0.19
BayesDel_addAF
Pathogenic
0.16
D
BayesDel_noAF
Pathogenic
0.19
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.43
.;T
Eigen
Uncertain
0.38
Eigen_PC
Uncertain
0.36
FATHMM_MKL
Uncertain
0.80
D
LIST_S2
Uncertain
0.93
D;D
M_CAP
Pathogenic
0.71
D
MetaRNN
Uncertain
0.74
D;D
MetaSVM
Pathogenic
0.98
D
MutationAssessor
Benign
1.5
.;L
PhyloP100
1.7
PrimateAI
Uncertain
0.77
T
PROVEAN
Benign
-1.4
N;N
REVEL
Pathogenic
0.67
Sift
Benign
0.17
T;T
Sift4G
Uncertain
0.060
T;T
Polyphen
1.0
D;D
Vest4
0.51
MVP
0.84
MPC
0.69
ClinPred
0.62
D
GERP RS
5.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.9
Varity_R
0.11
gMVP
0.61
Mutation Taster
=75/25
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: rs199473543; hg19: chr7-150644465; COSMIC: COSV51177688; COSMIC: COSV51177688; API