7-150948462-G-C

Position:

• chr7-150948462-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000238.4(KCNH2):​c.2674C>G​(p.Arg892Gly) variant causes a missense 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 Uncertain significance (★).

• Frequency: Genomes: not found (cov: 31)
• Consequence: KCNH2 NM_000238.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.64

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 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNH2	NM_000238.4	c.2674C>G	p.Arg892Gly	missense_variant	11/15	ENST00000262186.10	NP_000229.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNH2	ENST00000262186.10	c.2674C>G	p.Arg892Gly	missense_variant	11/15	1	NM_000238.4	ENSP00000262186.5
KCNH2	ENST00000330883.9	c.1654C>G	p.Arg552Gly	missense_variant	7/11	1		ENSP00000328531.4
KCNH2	ENST00000684241.1	n.3507C>G		non_coding_transcript_exon_variant	9/13

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 37

GnomAD4 genome Cov.: 31

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Long QT syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 01, 2021

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: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals affected with KCNH2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 892 of the KCNH2 protein (p.Arg892Gly). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.51
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.58	.;D
Eigen	Benign	0.17
Eigen_PC	Benign	0.18
FATHMM_MKL	Uncertain	0.85	D
LIST_S2	Uncertain	0.95	D;D
M_CAP	Pathogenic	0.92	D
MetaRNN	Uncertain	0.49	T;T
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Benign	1.8	.;L
PrimateAI	Uncertain	0.55	T
PROVEAN	Uncertain	-3.2	D;D
REVEL	Pathogenic	0.79
Sift	Benign	0.13	T;T
Sift4G	Benign	0.32	T;T
Polyphen		0.30	B;P
Vest4		0.34
MutPred		0.33		.;Loss of solvent accessibility (P = 0.0146);
MVP		0.95
MPC		0.62
ClinPred		0.98	D
GERP RS		3.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.9
Varity_R		0.44
gMVP		0.90

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

LitVar

Other links and lift over

dbSNP: rs201627778; hg19: chr7-150645550; COSMIC: COSV51125867; COSMIC: COSV51125867;