rs199472944

Variant names:

• chr7-150951552-G-A
• rs199472944
• NM_000238.4:c.1841C>T
• KCNH2 p.Ala614Val

Variant summary

Our verdict is

Pathogenic

>+14 Pathogenic

-7

-6

-1

0

+5

+6

+9

+10

BenignB

Likely BenignLB

UncertainVUS

Likely PathogenicLP

PathogenicP

. The variant received 21 ACMG points: 21P and 0B. PS3PM1PM2PP2PP3_StrongPP5_Very_Strong

The NM_000238.4(KCNH2):​c.1841C>T​(p.Ala614Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,872 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/23 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). ClinVar reports functional evidence for this variant: "SCV002767865: "In addition, functional studies show that this variant causes LQTS through dominant negative mechanism (PMID:9721698, 21240260)."" and additional evidence is available in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A614T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: KCNH2 NM_000238.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:10 O:1
• Conservation: PhyloP100: 9.85
• Publications: 74 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: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• 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: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Brugada syndrome

  Inheritance: AD Classification: MODERATE, NO_KNOWN Submitted by: Genomics England PanelApp, ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 21 ACMG points.

• PS3: PS3 evidence extracted from ClinVar submissions: SCV002767865: "In addition, functional studies show that this variant causes LQTS through dominant negative mechanism (PMID: 9721698, 21240260)."; SCV000321765: Published functional studies demonstrate a damaging effect as this variant exerts a dominant negative effect (Anderson et al., 2006; Sakaguchi et al., 2008; Itzhaki et al., 2011; Jou et al., 2013); SCV000543482: Experimental studies have shown that this missense change affects KCNH2 function (PMID: 16432067, 19057127, 23303164, 25417810).; SCV000917558: Several publications report experimental evidence evaluating an impact on protein function, such as electrophysiological findings (Itzhaki_2011) and intracellular trafficking (Anderson_2006), both of which were impaired in the presence of the variant.; SCV002715094: Numerous functional studies have demonstrated this alteration results in prolonged action-potential duration due to the loss of function of the IKr channel by deficient intracellular protein transport to the cell surface membrane (Nakajima T et al. Circ. Res., 1998 Aug;83:415-22; Sakaguchi T et al. J. Pharmacol. Sci., 2008 Dec;108:462-71; Itzhaki I et al. Nature, 2011 Mar;471:225-9; Jou CJ et al. Circ. Res., 2013 Mar;112:826-30).
• PM1: In a hotspot region, there are 18 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 20 uncertain in NM_000238.4
• 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 short QT syndrome type 1, long QT syndrome 2, short QT syndrome, Brugada syndrome, long QT syndrome.
• PP3: REVEL computational evidence supports a deleterious effect, 0.961
• PP5: Variant 7-150951552-G-A is Pathogenic according to our data. Variant chr7-150951552-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 29777.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

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.1841C>T	p.Ala614Val	missense	Exon 7 of 15	NP_000229.1	A0A090N8Q0
	KCNH2	NM_001406753.1		c.1553C>T	p.Ala518Val	missense	Exon 5 of 13	NP_001393682.1	Q12809-7
	KCNH2	NM_172056.3		c.1841C>T	p.Ala614Val	missense	Exon 7 of 9	NP_742053.1	Q12809-5

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	ENST00000262186.10	TSL:1 MANE Select	c.1841C>T	p.Ala614Val	missense	Exon 7 of 15	ENSP00000262186.5	Q12809-1
	KCNH2	ENST00000330883.9	TSL:1	c.821C>T	p.Ala274Val	missense	Exon 3 of 11	ENSP00000328531.4	Q12809-2
	KCNH2	ENST00000461280.2	TSL:1	n.1139C>T		non_coding_transcript_exon	Exon 3 of 5

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461872 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 727240

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 34

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
5	-	-	Long QT syndrome 2 (5)
3	-	-	Long QT syndrome (3)
1	-	-	Cardiovascular phenotype (1)
1	-	-	not provided (1)
-	-	-	Congenital long QT syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
CardioboostArm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.98	D
Eigen	Pathogenic	0.79
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.92	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.6	H
PhyloP100		9.8
PrimateAI	Pathogenic	0.79	T
PROVEAN	Uncertain	-3.9	D
REVEL	Pathogenic	0.96
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0020	D
Varity_R		0.80
gMVP		0.99
Mutation Taster		=18/82	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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

dbSNP: rs199472944;

hg19: chr7-150648640;

COSMIC: COSV51224186;

ACMG debug oncogenicity

ACGS debug oncogenicity

ACMG debug germline