rs758530960

Positions:

chr20-63406984-C-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP2BS2

The NM_172107.4(KCNQ2):c.2279G>A(p.Arg760His) variant causes a missense change. The variant allele was found at a frequency of 0.0000217 in 1,521,882 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000023 ( 0 hom. )

Consequence

KCNQ2
NM_172107.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2O:1

Conservation

PhyloP100: 4.38

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 Likely_benign. Variant got -3 ACMG points.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), KCNQ2. . Gene score misZ 4.0411 (greater than the threshold 3.09). Trascript score misZ 3.6968 (greater than threshold 3.09). GenCC has associacion of gene with seizures, benign familial neonatal, 1, neonatal-onset developmental and epileptic encephalopathy, benign familial neonatal-infantile seizures, benign neonatal seizures, malignant migrating partial seizures of infancy, neonatal encephalopathy with non-epileptic myoclonus, complex neurodevelopmental disorder, seizures, benign familial neonatal, 2, developmental and epileptic encephalopathy, 7, benign familial infantile epilepsy.

BS2

High AC in GnomAdExome4 at 31 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNQ2	NM_172107.4 linkuse as main transcript	c.2279G>A	p.Arg760His	missense_variant	17/17	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.2279G>A	p.Arg760His	missense_variant	17/17	1	NM_172107.4	ENSP00000352035.2		O43526-1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152192

Hom.:

Cov.:

show subpopulations

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:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000657

AC:

AN:

121808

Hom.:

AF XY:

0.0000602

AC XY:

AN XY:

66412

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000834

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000955

Gnomad SAS exome

AF:

0.0000988

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000664

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000226

AC:

AN:

1369690

Hom.:

Cov.:

AF XY:

0.0000208

AC XY:

AN XY:

673986

show subpopulations

Gnomad4 AFR exome

AF:

0.0000319

Gnomad4 AMR exome

AF:

0.0000568

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000281

Gnomad4 SAS exome

AF:

0.0000259

Gnomad4 FIN exome

AF:

0.0000571

Gnomad4 NFE exome

AF:

0.0000215

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152192

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74344

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.00000756

ExAC

AF:

0.0000634

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2Other:1

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Early infantile epileptic encephalopathy with suppression bursts

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 19, 2023

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 760 of the KCNQ2 protein (p.Arg760His). This variant is present in population databases (rs758530960, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with KCNQ2-related conditions. ClinVar contains an entry for this variant (Variation ID: 216827). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. Experimental studies have shown that this missense change does not substantially affect KCNQ2 function (PMID: 35104249). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Revvity Omics, Revvity

Jan 02, 2022

- -

Complex neurodevelopmental disorder

Other:1

not provided, no classification provided

literature only

Channelopathy-Associated Epilepsy Research Center

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Uncertain

0.11

BayesDel_noAF

Uncertain

0.13

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.019

.;T;T;T;.;.

Eigen

Uncertain

0.31

Eigen_PC

Uncertain

0.28

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.96

D;D;D;D;D;D

M_CAP

Pathogenic

0.85

MetaRNN

Uncertain

0.61

D;D;D;D;D;D

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.1

.;.;M;.;.;.

PrimateAI

Uncertain

0.74

PROVEAN

Benign

-1.6

.;.;N;.;N;.

REVEL

Uncertain

0.64

Sift

Uncertain

0.010

.;.;D;.;D;.

Sift4G

Benign

0.11

T;.;T;T;T;T

Polyphen

0.99

D;.;D;.;D;D

Vest4

0.39

MutPred

0.39

.;.;Loss of methylation at R760 (P = 0.0215);.;.;.;

MVP

0.75

MPC

1.8

ClinPred

0.21

GERP RS

5.0

Varity_R

0.18

gMVP

0.47

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