7-150974925-G-A

Variant names:

• chr7-150974925-G-A
• rs745885744
• NM_000238.4:c.93C>T

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_Moderate BP6_Very_Strong BP7 BS2_Supporting

The NM_000238.4(KCNH2):​c.93C>T​(p.Ile31Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000055 in 1,454,672 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Synonymous variant affecting the same amino acid position (i.e. I31I) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: KCNH2 NM_000238.4 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: 0.834
• 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 -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.33).
• BP6: Variant 7-150974925-G-A is Benign according to our data. Variant chr7-150974925-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 456943.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=0.834 with no splicing effect.
• BS2: High AC in GnomAdExome4 at 8 AD gene. Variant has AC lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

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.93C>T	p.Ile31Ile	synonymous	Exon 2 of 15	NP_000229.1
	KCNH2	NM_001406755.1		c.-85C>T		5_prime_UTR_premature_start_codon_gain	Exon 2 of 9	NP_001393684.1
	KCNH2	NM_172056.3		c.93C>T	p.Ile31Ile	synonymous	Exon 2 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.93C>T	p.Ile31Ile	synonymous	Exon 2 of 15	ENSP00000262186.5
	KCNH2	ENST00000713710.1		c.93C>T	p.Ile31Ile	synonymous	Exon 2 of 15	ENSP00000519013.1
	KCNH2	ENST00000532957.5	TSL:2	n.316C>T		non_coding_transcript_exon	Exon 2 of 9

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD2 exomes AF: 0.00000421 AC: 1 AN: 237524 AF XY: 0.00000772

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000940

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000550 AC: 8 AN: 1454672 Hom.: 0 Cov.: 34 AF XY: 0.00000553 AC XY: 4 AN XY: 723332

African (AFR) AF: 0.00 AC: 0 AN: 33360

American (AMR) AF: 0.00 AC: 0 AN: 44394

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26034

East Asian (EAS) AF: 0.00 AC: 0 AN: 39522

South Asian (SAS) AF: 0.00 AC: 0 AN: 85850

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 49868

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5730

European-Non Finnish (NFE) AF: 0.00000721 AC: 8 AN: 1109760

Other (OTH) AF: 0.00 AC: 0 AN: 60154

GnomAD4 genome Cov.: 34

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Long QT syndrome Benign:1

May 09, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Cardiovascular phenotype Benign:1

Jun 24, 2020

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.33
CADD	Benign	13
DANN	Benign	0.97
PhyloP100		0.83
Mutation Taster		=100/0	polymorphism

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: rs745885744; hg19: chr7-150672013;