7-150974885-T-C

Variant names:

• chr7-150974885-T-C
• rs199472839
• NM_000238.4:c.133A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_000238.4(KCNH2):​c.133A>G​(p.Asn45Asp) variant causes a missense change. 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. N45Y) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: KCNH2 NM_000238.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.13
• 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: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 19 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 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, 0.98

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNH2	NM_000238.4	c.133A>G	p.Asn45Asp	missense_variant	Exon 2 of 15	ENST00000262186.10	NP_000229.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNH2	ENST00000262186.10	c.133A>G	p.Asn45Asp	missense_variant	Exon 2 of 15	1	NM_000238.4	ENSP00000262186.5
KCNH2	ENST00000713710.1	c.133A>G	p.Asn45Asp	missense_variant	Exon 2 of 15			ENSP00000519013.1
KCNH2	ENST00000532957.5	n.356A>G		non_coding_transcript_exon_variant	Exon 2 of 9	2
KCNH2	ENST00000713700.1	n.91A>G		non_coding_transcript_exon_variant	Exon 2 of 9

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 33

Alfa AF: 0.000129 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
CardioboostArm	Uncertain	0.52
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.96	D
Eigen	Benign	0.094
Eigen_PC	Benign	0.030
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.3	H
PhyloP100		6.1
PrimateAI	Pathogenic	0.87	D
PROVEAN	Uncertain	-3.3	D
REVEL	Uncertain	0.63
Sift	Uncertain	0.0040	D
Sift4G	Uncertain	0.015	D
Polyphen		0.085	B
Vest4		0.84
MutPred		0.83		Loss of helix (P = 0.1299);
MVP		0.98
MPC		1.5
ClinPred		0.92	D
GERP RS		1.6
Varity_R		0.96
gMVP		0.98
Mutation Taster		=6/94	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: rs199472839; hg19: chr7-150671973;