7-150947477-C-G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 7P and 1B. PM1PM2PP2PP3_ModerateBS2_Supporting

The NM_000238.4(KCNH2):​c.3003G>C​(p.Trp1001Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000035 in 1,427,632 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 nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. W1001S) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0000035 ( 0 hom. )

Consequence

KCNH2
NM_000238.4 missense

Scores

10
8
2

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.86

Publications

14 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_pathogenic. The variant received 6 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
PM2
Very rare variant in population databases, with high coverage;
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, 0.907
BS2
High AC in GnomAdExome4 at 5 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.3003G>C p.Trp1001Cys 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.3003G>C p.Trp1001Cys missense_variant Exon 13 of 15 1 NM_000238.4 ENSP00000262186.5 Q12809-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD2 exomes
AF:
0.00000524
AC:
1
AN:
190766
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:
0.0000122
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000350
AC:
5
AN:
1427632
Hom.:
0
Cov.:
36
AF XY:
0.00000141
AC XY:
1
AN XY:
706916
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33044
American (AMR)
AF:
0.00
AC:
0
AN:
38634
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25444
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38326
South Asian (SAS)
AF:
0.0000122
AC:
1
AN:
81750
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
49604
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5722
European-Non Finnish (NFE)
AF:
0.00000365
AC:
4
AN:
1095942
Other (OTH)
AF:
0.00
AC:
0
AN:
59166
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.445
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

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.:
33
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Long QT syndrome Uncertain:1
Dec 27, 2019
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with KCNH2-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces tryptophan with cysteine at codon 1001 of the KCNH2 protein (p.Trp1001Cys). The tryptophan residue is moderately conserved and there is a large physicochemical difference between tryptophan and cysteine. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.93
CardioboostArm
Uncertain
0.16
BayesDel_addAF
Pathogenic
0.52
D
BayesDel_noAF
Pathogenic
0.50
CADD
Pathogenic
28
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.91
.;D
Eigen
Uncertain
0.67
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.95
D;D
M_CAP
Pathogenic
0.62
D
MetaRNN
Pathogenic
0.91
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
1.9
.;L
PhyloP100
5.9
PrimateAI
Pathogenic
0.88
D
PROVEAN
Pathogenic
-6.4
D;D
REVEL
Pathogenic
0.94
Sift
Uncertain
0.0010
D;D
Sift4G
Uncertain
0.043
D;D
Polyphen
1.0
D;D
Vest4
0.71
MutPred
0.73
.;Gain of sheet (P = 0.0101);
MVP
0.96
MPC
0.87
ClinPred
0.99
D
GERP RS
4.9
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.83
gMVP
0.82
Mutation Taster
=56/44
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.22
Details are displayed if max score is > 0.2
DS_AG_spliceai
0.22
Position offset: 6

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs121912509; hg19: chr7-150644565; API