KCNH2 p.Val822Leu

Variant names:

• chr7-150948984-C-A
• NM_000238.4:c.2464G>T
• KCNH2 p.Val822Leu

Your query was ambiguous. Multiple possible variants found:

• chr7-150948984-C-A
• chr7-150948984-C-G
• chr7-150948982-CAC-TAA
• chr7-150948982-CAC-AAG
• chr7-150948982-CAC-GAG
• chr7-150948982-CAC-TAG

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PS1_Very_Strong PM1 PM2 PM5 PP2 PP3_Moderate

The NM_000238.4(KCNH2):​c.2464G>T​(p.Val822Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. V822M) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: KCNH2 NM_000238.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.90
• Publications: 0 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: Pathogenic. The variant received 17 ACMG points.

• PS1: Transcript NM_000238.4 (KCNH2) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 17 uncertain in NM_000238.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-150948984-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 14424.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• 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, short QT syndrome type 1, short QT syndrome, Brugada syndrome, long QT syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.908

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.2464G>T	p.Val822Leu	missense	Exon 10 of 15	NP_000229.1	A0A090N8Q0
	KCNH2	NM_001406753.1		c.2176G>T	p.Val726Leu	missense	Exon 8 of 13	NP_001393682.1	Q12809-7
	KCNH2	NM_172057.3		c.1444G>T	p.Val482Leu	missense	Exon 6 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.2464G>T	p.Val822Leu	missense	Exon 10 of 15	ENSP00000262186.5	Q12809-1
	KCNH2	ENST00000330883.9	TSL:1	c.1444G>T	p.Val482Leu	missense	Exon 6 of 11	ENSP00000328531.4	Q12809-2
	KCNH2	ENST00000713710.1		c.2398G>T	p.Val800Leu	missense	Exon 10 of 15	ENSP00000519013.1	A0AAQ5BGR0

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
CardioboostArm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	D
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.97	D
M_CAP	Pathogenic	0.71	D
MetaRNN	Pathogenic	0.91	D
MetaSVM	Pathogenic	0.97	D
MutationAssessor	Pathogenic	3.0	M
PhyloP100		7.9
PrimateAI	Pathogenic	0.86	D
PROVEAN	Uncertain	-2.8	D
REVEL	Pathogenic	0.87
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0050	D
Varity_R		0.77
gMVP		0.95
Mutation Taster		=2/98	disease causing

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr7-150646072;