rs794728469

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000238.4(KCNH2):​c.3107delG​(p.Gly1036AlafsTer21) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. G1036G) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

KCNH2
NM_000238.4 frameshift

Scores

Not classified

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 1.40

Publications

5 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: Pathogenic. The variant received 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 7-150947372-GC-G is Pathogenic according to our data. Variant chr7-150947372-GC-G is described in ClinVar as Pathogenic. ClinVar VariationId is 200801.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNH2NM_000238.4 linkc.3107delG p.Gly1036AlafsTer21 frameshift_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.3107delG p.Gly1036AlafsTer21 frameshift_variant Exon 13 of 15 1 NM_000238.4 ENSP00000262186.5 Q12809-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1395090
Hom.:
0
Cov.:
36
AF XY:
0.00
AC XY:
0
AN XY:
688188
African (AFR)
AF:
0.00
AC:
0
AN:
31684
American (AMR)
AF:
0.00
AC:
0
AN:
35666
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25116
East Asian (EAS)
AF:
0.00
AC:
0
AN:
35916
South Asian (SAS)
AF:
0.00
AC:
0
AN:
79144
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
45542
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5186
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1078954
Other (OTH)
AF:
0.00
AC:
0
AN:
57882
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Pathogenic:1
Jun 16, 2022
GeneDx
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Frameshift variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Reported in individuals with suspicion of long QT syndrome or affected with sudden arrhythmic death syndrome (Lieve et al., 2013; Lahrouchi et al., 2017); Not observed at significant frequency in large population cohorts (gnomAD); This variant is associated with the following publications: (PMID: 23631430, 28449774) -

Long QT syndrome Pathogenic:1
Nov 10, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change creates a premature translational stop signal (p.Gly1036Alafs*21) in the KCNH2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in KCNH2 are known to be pathogenic (PMID: 10973849, 19862833). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individuals with suspicion of long QT syndrome or sudden arrhythmic death syndrome (PMID: 23631430, 28449774). ClinVar contains an entry for this variant (Variation ID: 200801). For these reasons, this variant has been classified as Pathogenic. -

Cardiovascular phenotype Pathogenic:1
May 31, 2018
Ambry Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.3107delG pathogenic mutation, located in coding exon 13 of the KCNH2 gene, results from a deletion of one nucleotide at position 3107, causing a translational frameshift with a predicted alternate stop codon (p.G1036Afs*21). This alteration has been reported in a long QT syndrome (LQTS) cohort and a sudden death cohort (Lieve KV et al. Genet Test Mol Biomarkers, 2013 Jul;17:553-61; Lahrouchi N et al. J. Am. Coll. Cardiol., 2017 May;69:2134-2145). In addition to the clinical data presented in the literature, this alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
1.4
Mutation Taster
=1/199
disease causing (ClinVar)

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.11
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: rs794728469; hg19: chr7-150644460; API