chr7-150951648-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 5P and 4B. PM1PM5PP2BS2

The NM_000238.4(KCNH2):​c.1745G>A​(p.Arg582His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,461,870 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. R582P) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 34)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

2
7
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: -0.0770

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 1 ACMG points.

PM1
In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 21 uncertain in NM_000238.4
PM5
Other missense variant is known to change same aminoacid residue: Variant chr7-150951649-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 14428.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
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 19 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.1745G>A p.Arg582His missense_variant Exon 7 of 15 ENST00000262186.10 NP_000229.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNH2ENST00000262186.10 linkc.1745G>A p.Arg582His missense_variant Exon 7 of 15 1 NM_000238.4 ENSP00000262186.5

Frequencies

GnomAD3 genomes
Cov.:
34
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251404
AF XY:
0.0000221
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:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461870
Hom.:
0
Cov.:
34
AF XY:
0.0000193
AC XY:
14
AN XY:
727236
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53400
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000144
AC:
16
AN:
1112008
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
2
4
6
8
10
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
Cov.:
34
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:1
Jul 07, 2023
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 histidine, which is basic and polar, at codon 582 of the KCNH2 protein (p.Arg582His). This variant is present in population databases (rs199473426, gnomAD 0.003%). 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. This variant disrupts the p.Arg582 amino acid residue in KCNH2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 10220144, 21376840, 22949429). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Not Available". The histidine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. ClinVar contains an entry for this variant (Variation ID: 926210). This variant has not been reported in the literature in individuals affected with KCNH2-related conditions.

Cardiac arrhythmia Uncertain:1
Jan 30, 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 histidine at codon 582 of the KCNH2 protein. Computational prediction suggests that this variant may have deleterious impact on protein structure and function (internally defined REVEL score threshold >= 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 KCNH2-related disorders in the literature. This variant has been identified in 3/251404 chromosomes in the general population by the Genome Aggregation Database (gnomAD). A different missense variant occurring at the same codon, p.Arg582Cys, is known to be pathogenic (Clinvar variation ID 14428), indicating that arginine at this position is important for KCNH2 protein function. 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
0.081
CardioboostArm
Benign
0.019
BayesDel_addAF
Uncertain
0.092
D
BayesDel_noAF
Uncertain
-0.010
CADD
Benign
17
DANN
Uncertain
1.0
DEOGEN2
Benign
0.0
.;D;D
Eigen
Benign
-0.20
Eigen_PC
Benign
-0.20
FATHMM_MKL
Benign
0.44
N
LIST_S2
Benign
0.79
T;T;T
M_CAP
Pathogenic
0.68
D
MetaRNN
Uncertain
0.71
D;D;D
MetaSVM
Uncertain
0.76
D
MutationAssessor
Benign
0.0
.;L;.
PhyloP100
-0.077
PrimateAI
Benign
0.32
T
PROVEAN
Uncertain
-2.8
D;D;.
REVEL
Pathogenic
0.74
Sift
Benign
0.061
T;T;.
Sift4G
Uncertain
0.022
D;D;T
Vest4
0.33
ClinPred
0.87
D
GERP RS
3.5
Varity_R
0.071
gMVP
0.65
Mutation Taster
=57/43
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: rs199473426; hg19: chr7-150648736; COSMIC: COSV51126911; API