7-150948501-C-G

Variant names:

• chr7-150948501-C-G
• rs199473040
• NM_000238.4:c.2635G>C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_000238.4(KCNH2):​c.2635G>C​(p.Gly879Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 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. G879D) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 31)
• Consequence: KCNH2 NM_000238.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3 O:1
• Conservation: PhyloP100: 0.0610
• Publications: 1 publications found

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), G2P, Ambry Genetics
• short QT syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• 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

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• 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.
• BP4: Computational evidence support a benign effect (MetaRNN=0.41040334).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000238.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	NM_000238.4	MANE Select	c.2635G>C	p.Gly879Arg	missense	Exon 11 of 15	NP_000229.1	A0A090N8Q0
	KCNH2	NM_001406753.1		c.2347G>C	p.Gly783Arg	missense	Exon 9 of 13	NP_001393682.1	Q12809-7
	KCNH2	NM_172057.3		c.1615G>C	p.Gly539Arg	missense	Exon 7 of 11	NP_742054.1	Q12809-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	ENST00000262186.10	TSL:1 MANE Select	c.2635G>C	p.Gly879Arg	missense	Exon 11 of 15	ENSP00000262186.5	Q12809-1
	KCNH2	ENST00000330883.9	TSL:1	c.1615G>C	p.Gly539Arg	missense	Exon 7 of 11	ENSP00000328531.4	Q12809-2
	KCNH2	ENST00000713710.1		c.2569G>C	p.Gly857Arg	missense	Exon 11 of 15	ENSP00000519013.1	A0AAQ5BGR0

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 37

GnomAD4 genome Cov.: 31

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Cardiovascular phenotype (1)
-	1	-	Long QT syndrome (1)
-	1	-	Short QT syndrome type 1;C3150943:Long QT syndrome 2 (1)
-	-	-	Congenital long QT syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
CardioboostArm	Benign	0.0000056
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.070
CADD	Benign	18
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.54	D
Eigen	Benign	-0.58
Eigen_PC	Benign	-0.60
FATHMM_MKL	Benign	0.32	N
LIST_S2	Benign	0.85	D
M_CAP	Pathogenic	0.56	D
MetaRNN	Benign	0.41	T
MetaSVM	Uncertain	0.51	D
MutationAssessor	Benign	1.5	L
PhyloP100		0.061
PrimateAI	Benign	0.46	T
PROVEAN	Uncertain	-2.4	N
REVEL	Uncertain	0.61
Sift	Benign	0.12	T
Sift4G	Benign	0.24	T
Polyphen		0.031	B
Vest4		0.39
MutPred		0.28		Gain of solvent accessibility (P = 0.0171)
MVP		0.94
MPC		0.23
ClinPred		0.48	T
GERP RS		2.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.3
Varity_R		0.13
gMVP		0.79
Mutation Taster		=77/23	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs199473040; hg19: chr7-150645589;