rs199473528

Variant names:

• chr7-150951481-T-C
• rs199473528
• NM_000238.4:c.1912A>G

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5

The NM_000238.4(KCNH2):​c.1912A>G​(p.Lys638Glu) 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. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. K638N) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 34)
• Consequence: KCNH2 NM_000238.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:1 O:1
• Conservation: PhyloP100: 7.68
• Publications: 7 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), Ambry Genetics, G2P
• short QT syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• 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 12 ACMG points.

• PM1: In a hotspot region, there are 18 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 29 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 chr7-150951480-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 200395.Status of the report is criteria_provided_single_submitter, 1 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, Brugada syndrome, short QT syndrome type 1, short QT syndrome, long QT syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988
• PP5: Variant 7-150951481-T-C is Pathogenic according to our data. Variant chr7-150951481-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 67332.

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.1912A>G	p.Lys638Glu	missense	Exon 7 of 15	NP_000229.1
	KCNH2	NM_001406753.1		c.1624A>G	p.Lys542Glu	missense	Exon 5 of 13	NP_001393682.1
	KCNH2	NM_172056.3		c.1912A>G	p.Lys638Glu	missense	Exon 7 of 9	NP_742053.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	ENST00000262186.10	TSL:1 MANE Select	c.1912A>G	p.Lys638Glu	missense	Exon 7 of 15	ENSP00000262186.5
	KCNH2	ENST00000330883.9	TSL:1	c.892A>G	p.Lys298Glu	missense	Exon 3 of 11	ENSP00000328531.4
	KCNH2	ENST00000461280.2	TSL:1	n.1210A>G		non_coding_transcript_exon	Exon 3 of 5

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 34

ClinVar

ClinVar submissions as Germline

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	-	Long QT syndrome (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	0.58
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.98	D
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Pathogenic	0.95	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.6	H
PhyloP100		7.7
PrimateAI	Pathogenic	0.86	D
PROVEAN	Uncertain	-3.9	D
REVEL	Pathogenic	0.88
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		0.99	D
Vest4		0.93
MutPred		0.88		Loss of ubiquitination at K638 (P = 0.0155)
MVP		1.0
MPC		2.5
ClinPred		1.0	D
GERP RS		3.0
Varity_R		0.95
gMVP		0.99
Mutation Taster		=10/90	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

Other links and lift over

dbSNP: rs199473528; hg19: chr7-150648569;