7-150947832-C-G

Variant names:

• chr7-150947832-C-G
• rs776097223
• NM_000238.4:c.2739G>C

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_Moderate BP7 BS2

The NM_000238.4(KCNH2):​c.2739G>C​(p.Ala913Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000656 in 1,525,506 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. A913A) has been classified as Benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000066 (0 hom.)
• Consequence: KCNH2 NM_000238.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.81
• 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), 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: Benign. The variant received -7 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.41).
• BP7: Synonymous conserved (PhyloP=-1.82 with no splicing effect.
• BS2: High AC in GnomAdExome4 at 9 AD gene.

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.2739G>C	p.Ala913Ala	synonymous	Exon 12 of 15	NP_000229.1
	KCNH2	NM_001406753.1		c.2451G>C	p.Ala817Ala	synonymous	Exon 10 of 13	NP_001393682.1
	KCNH2	NM_172057.3		c.1719G>C	p.Ala573Ala	synonymous	Exon 8 of 11	NP_742054.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNH2	ENST00000262186.10	TSL:1 MANE Select	c.2739G>C	p.Ala913Ala	synonymous	Exon 12 of 15	ENSP00000262186.5
	KCNH2	ENST00000330883.9	TSL:1	c.1719G>C	p.Ala573Ala	synonymous	Exon 8 of 11	ENSP00000328531.4
	KCNH2	ENST00000713710.1		c.2673G>C	p.Ala891Ala	synonymous	Exon 12 of 15	ENSP00000519013.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152224 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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 AF: 0.00000655 AC: 9 AN: 1373282 Hom.: 0 Cov.: 36 AF XY: 0.0000103 AC XY: 7 AN XY: 676890

African (AFR) AF: 0.00 AC: 0 AN: 31252

American (AMR) AF: 0.00 AC: 0 AN: 34356

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24304

East Asian (EAS) AF: 0.00 AC: 0 AN: 35572

South Asian (SAS) AF: 0.0000258 AC: 2 AN: 77390

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 34836

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4062

European-Non Finnish (NFE) AF: 0.00000652 AC: 7 AN: 1074240

Other (OTH) AF: 0.00 AC: 0 AN: 57270

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152224 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74368

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000241 AC: 1 AN: 41448

American (AMR) AF: 0.00 AC: 0 AN: 15292

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.00 AC: 0 AN: 4836

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10628

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 314

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68034

Other (OTH) AF: 0.00 AC: 0 AN: 2094

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.41
CADD	Benign	5.2
DANN	Benign	0.81
PhyloP100		-1.8

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: rs776097223; hg19: chr7-150644920;