rs199473029

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 3P and 4B. PP2PP3_ModerateBS2

The NM_000238.4(KCNH2):​c.3233A>G​(p.Tyr1078Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000348 in 1,609,706 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 (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

9
9
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3O:1

Conservation

PhyloP100: 2.57

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.

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, 0.915
BS2
High AC in GnomAdExome4 at 53 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.3233A>G p.Tyr1078Cys missense_variant Exon 14 of 15 ENST00000262186.10 NP_000229.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNH2ENST00000262186.10 linkc.3233A>G p.Tyr1078Cys missense_variant Exon 14 of 15 1 NM_000238.4 ENSP00000262186.5

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
151938
Hom.:
0
Cov.:
32
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000401
AC:
1
AN:
249410
AF XY:
0.00
show subpopulations
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:
0.00000889
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000364
AC:
53
AN:
1457768
Hom.:
0
Cov.:
32
AF XY:
0.0000373
AC XY:
27
AN XY:
724480
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33436
American (AMR)
AF:
0.00
AC:
0
AN:
44532
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26040
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39562
South Asian (SAS)
AF:
0.00
AC:
0
AN:
85950
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53168
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5736
European-Non Finnish (NFE)
AF:
0.0000397
AC:
44
AN:
1109150
Other (OTH)
AF:
0.000150
AC:
9
AN:
60194
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
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:
0.0000197
AC:
3
AN:
151938
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74216
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41334
American (AMR)
AF:
0.00
AC:
0
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5172
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4812
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
67952
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000850
Hom.:
0
Bravo
AF:
0.0000227

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jul 26, 2016
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant identified in a genome or exome case(s) and assessed due to predicted null impact of the variant or pathogenic assertions in the literature or databases. Disclaimer: This variant has not undergone full assessment. The following are preliminary notes: Reported in 1 LQT proband (PMID 19716085), functional study (PMID 25417810) shows this variant does not impact trafficking -

Long QT syndrome Uncertain:1
Dec 07, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 1078 of the KCNH2 protein (p.Tyr1078Cys). This variant is present in population databases (rs199473029, gnomAD 0.002%). This missense change has been observed in individual(s) with KCNH2-related conditions (PMID: 19716085). ClinVar contains an entry for this variant (Variation ID: 67483). 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. Experimental studies have shown that this missense change does not substantially affect KCNH2 function (PMID: 19841300, 25348405, 25417810). 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
Nov 12, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

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:19716085). 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
Uncertain
0.50
CardioboostArm
Pathogenic
0.95
BayesDel_addAF
Pathogenic
0.38
D
BayesDel_noAF
Pathogenic
0.32
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.90
.;D
Eigen
Uncertain
0.64
Eigen_PC
Uncertain
0.60
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.96
D;D
M_CAP
Pathogenic
0.72
D
MetaRNN
Pathogenic
0.92
D;D
MetaSVM
Uncertain
0.66
D
MutationAssessor
Benign
1.9
.;L
PhyloP100
2.6
PrimateAI
Pathogenic
0.79
T
PROVEAN
Pathogenic
-5.8
D;D
REVEL
Pathogenic
0.88
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.053
T;D
Polyphen
1.0
D;D
Vest4
0.76
MVP
0.92
MPC
0.77
ClinPred
0.99
D
GERP RS
4.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.74
gMVP
0.63
Mutation Taster
=4/96
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs199473029; hg19: chr7-150644062; API