7-150951013-G-C

Variant names:

• chr7-150951013-G-C
• rs778135438
• NM_000238.4:c.2053C>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM2 PM5 PP2 PP3_Moderate

The NM_000238.4(KCNH2):​c.2053C>G​(p.Arg685Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,250 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. 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. R685H) has been classified as Likely pathogenic.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: KCNH2 NM_000238.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.95
• Publications: 3 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 7 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-150951012-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 979129.
• 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, 0.923

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	NM_000238.4	MANE Select	c.2053C>G	p.Arg685Gly	missense	Exon 8 of 15	NP_000229.1
	KCNH2	NM_001406753.1		c.1765C>G	p.Arg589Gly	missense	Exon 6 of 13	NP_001393682.1
	KCNH2	NM_172056.3		c.2053C>G	p.Arg685Gly	missense	Exon 8 of 9	NP_742053.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	ENST00000262186.10	TSL:1 MANE Select	c.2053C>G	p.Arg685Gly	missense	Exon 8 of 15	ENSP00000262186.5
	KCNH2	ENST00000330883.9	TSL:1	c.1033C>G	p.Arg345Gly	missense	Exon 4 of 11	ENSP00000328531.4
	KCNH2	ENST00000461280.2	TSL:1	n.1351C>G		non_coding_transcript_exon	Exon 4 of 5

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152250 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 33

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152250 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74384

African (AFR) AF: 0.00 AC: 0 AN: 41476

American (AMR) AF: 0.0000654 AC: 1 AN: 15286

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5196

South Asian (SAS) AF: 0.00 AC: 0 AN: 4838

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68038

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

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	0.58	D
BayesDel_noAF	Pathogenic	0.59
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.75
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.86	D
MetaRNN	Pathogenic	0.92	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.4	M
PhyloP100		9.9
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-6.8	D
REVEL	Pathogenic	0.93
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.59		Loss of MoRF binding (P = 0.0072)
MVP		0.99
MPC		2.4
ClinPred		1.0	D
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.81
gMVP		0.97
Mutation Taster		=0/100	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: rs778135438; hg19: chr7-150648101;