20-63413524-G-A

Position:

chr20-63413524-G-A

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_172107.4(KCNQ2):c.1689C>T(p.Asp563Asp) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000955 in 1,613,512 control chromosomes in the GnomAD database, including 8 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0047 ( 3 hom., cov: 33)

Exomes 𝑓: 0.00056 ( 5 hom. )

Consequence

KCNQ2
NM_172107.4 synonymous

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:9O:1

Conservation

PhyloP100: -1.95

Variant links:

Genes affected

KCNQ2 (HGNC:6296): (potassium voltage-gated channel subfamily Q member 2) The M channel is a slowly activating and deactivating potassium channel that plays a critical role in the regulation of neuronal excitability. The M channel is formed by the association of the protein encoded by this gene and a related protein encoded by the KCNQ3 gene, both integral membrane proteins. M channel currents are inhibited by M1 muscarinic acetylcholine receptors and activated by retigabine, a novel anti-convulsant drug. Defects in this gene are a cause of benign familial neonatal convulsions type 1 (BFNC), also known as epilepsy, benign neonatal type 1 (EBN1). At least five transcript variants encoding five different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

KCNQ2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -21 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.82).

BP6

Variant 20-63413524-G-A is Benign according to our data. Variant chr20-63413524-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 138026.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr20-63413524-G-A is described in Lovd as [Likely_benign].

BP7

Synonymous conserved (PhyloP=-1.95 with no splicing effect.

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00475 (723/152320) while in subpopulation AFR AF= 0.0165 (686/41560). AF 95% confidence interval is 0.0155. There are 3 homozygotes in gnomad4. There are 339 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High AC in GnomAd4 at 723 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNQ2	NM_172107.4 linkuse as main transcript	c.1689C>T	p.Asp563Asp	synonymous_variant	15/17	ENST00000359125.7	NP_742105.1	O43526-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNQ2	ENST00000359125.7 linkuse as main transcript	c.1689C>T	p.Asp563Asp	synonymous_variant	15/17	1	NM_172107.4	ENSP00000352035.2		O43526-1

Frequencies

GnomAD3 genomes

AF:

0.00472

AC:

718

AN:

152202

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0164

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00164

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00316

Gnomad NFE

AF:

0.0000882

Gnomad OTH

AF:

0.00239

GnomAD3 exomes

AF:

0.00137

AC:

343

AN:

251180

Hom.:

AF XY:

0.00102

AC XY:

139

AN XY:

135854

show subpopulations

Gnomad AFR exome

AF:

0.0182

Gnomad AMR exome

AF:

0.000752

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000969

Gnomad OTH exome

AF:

0.00147

GnomAD4 exome

AF:

0.000560

AC:

818

AN:

1461192

Hom.:

Cov.:

AF XY:

0.000483

AC XY:

351

AN XY:

726896

show subpopulations

Gnomad4 AFR exome

AF:

0.0180

Gnomad4 AMR exome

AF:

0.000827

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000464

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000926

Gnomad4 OTH exome

AF:

0.00106

GnomAD4 genome

AF:

0.00475

AC:

723

AN:

152320

Hom.:

Cov.:

AF XY:

0.00455

AC XY:

339

AN XY:

74476

show subpopulations

Gnomad4 AFR

AF:

0.0165

Gnomad4 AMR

AF:

0.00163

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000882

Gnomad4 OTH

AF:

0.00237

Alfa

AF:

0.00296

Hom.:

Bravo

AF:

0.00563

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.000218

EpiControl

AF:

0.000119

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:9Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Benign:4

Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -
Likely benign, criteria provided, single submitter	not provided	Breakthrough Genomics, Breakthrough Genomics	-	- -
Likely benign, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	Aug 11, 2017	- -
Likely benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	-	- -

not specified

Benign:3

Benign, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	May 05, 2017	- -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Jan 31, 2013	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	Athena Diagnostics	Jan 06, 2020	- -

Inborn genetic diseases

Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 24, 2016

This alteration is classified as 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. -

Early infantile epileptic encephalopathy with suppression bursts

Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 30, 2024

- -

Developmental and epileptic encephalopathy, 7

Other:1

not provided, no classification provided

literature only

GeneReviews

EE (epileptic encephalopathy) -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.82

CADD

Benign

0.32

DANN

Benign

0.74

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over