rs140279503
Variant summary
Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM5BS2
The NM_000238.4(KCNH2):c.2659C>T(p.Arg887Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000255 in 1,610,562 control chromosomes in the GnomAD database, including 1 homozygotes. 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. R887H) has been classified as Pathogenic.
Frequency
Consequence
NM_000238.4 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Likely_benign. Variant got -2 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
KCNH2 | NM_000238.4 | c.2659C>T | p.Arg887Cys | missense_variant | Exon 11 of 15 | ENST00000262186.10 | NP_000229.1 |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
KCNH2 | ENST00000262186.10 | c.2659C>T | p.Arg887Cys | missense_variant | Exon 11 of 15 | 1 | NM_000238.4 | ENSP00000262186.5 | ||
KCNH2 | ENST00000330883.9 | c.1639C>T | p.Arg547Cys | missense_variant | Exon 7 of 11 | 1 | ENSP00000328531.4 | |||
KCNH2 | ENST00000684241.1 | n.3492C>T | non_coding_transcript_exon_variant | Exon 9 of 13 |
Frequencies
GnomAD3 genomes AF: 0.0000928 AC: 14AN: 150822Hom.: 0 Cov.: 31
GnomAD3 exomes AF: 0.0000402 AC: 10AN: 249022Hom.: 0 AF XY: 0.0000296 AC XY: 4AN XY: 134942
GnomAD4 exome AF: 0.0000185 AC: 27AN: 1459630Hom.: 1 Cov.: 37 AF XY: 0.0000234 AC XY: 17AN XY: 726252
GnomAD4 genome AF: 0.0000928 AC: 14AN: 150932Hom.: 0 Cov.: 31 AF XY: 0.000109 AC XY: 8AN XY: 73694
ClinVar
Submissions by phenotype
not provided Uncertain:2
- -
In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -
Long QT syndrome Uncertain:2
This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 887 of the KCNH2 protein (p.Arg887Cys). This variant is present in population databases (rs140279503, gnomAD 0.01%). 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: 193802). 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. -
This missense variant replaces arginine with cysteine at codon 887 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 cardiovascular disorders in the literature. This variant has been identified in 12/280278 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. -
Cardiovascular phenotype Uncertain:1
The p.R887C variant (also known as c.2659C>T), located in coding exon 11 of the KCNH2 gene, results from a C to T substitution at nucleotide position 2659. The arginine at codon 887 is replaced by cysteine, an amino acid with highly dissimilar properties, and is located in the C-terminal region of the protein. An alternate amino acid substitution at this codon, p.R887H, was described in a long QT syndrome genetic testing cohort and in a primary electrical syndrome cohort (Tester et al. Heart Rhythm. 2005;2(5):507-17; Adler A et al. Circ Arrhythm Electrophysiol. 2016;9:e003440). Based on data from gnomAD, the frequency for this variant is above the maximum credible frequency for a disease-causing variant in this gene based on internally established thresholds (Karczewski et al. Nature. 2020 May;581(7809):434-443; Whiffin et al. Genet Med. 2017 10;19:1151-1158). This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is conflicting at this time, the clinical significance of this alteration remains unclear. -
Short QT syndrome type 1;C3150943:Long QT syndrome 2 Uncertain:1
- -
Cardiac arrhythmia Uncertain:1
This missense variant replaces arginine with cysteine at codon 887 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 cardiovascular disorders in the literature. This variant has been identified in 12/280278 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:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at