Genetic Variant KCNQ2:p.Gly624Arg (chr20-63408430-C-T) – ACMG Classification: Uncertain_significance (0 pts)

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 4P and 4B. PM1PP2PP3BS2

The NM_172107.4(KCNQ2):c.1870G>A(p.Gly624Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000684 in 1,608,654 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G624W) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000069 ( 0 hom. )

Consequence

KCNQ2
NM_172107.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 4.72

Publications

3 publications found

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 Gene-Disease associations (from GenCC):

complex neurodevelopmental disorder
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
developmental and epileptic encephalopathy, 7
Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae)
neonatal encephalopathy with non-epileptic myoclonus
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
neonatal-onset developmental and epileptic encephalopathy
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
seizures, benign familial neonatal, 1
Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
undetermined early-onset epileptic encephalopathy
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
seizures, benign familial neonatal, 2
Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
benign familial infantile epilepsy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
benign familial neonatal-infantile seizures
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
benign neonatal seizures
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
malignant migrating partial seizures of infancy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

KCNQ2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

PM1

In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_172107.4

PP2

Missense variant in the KCNQ2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 319 curated pathogenic missense variants (we use a threshold of 10). The gene has 78 curated benign missense variants. Gene score misZ: 4.0411 (above the threshold of 3.09). Trascript score misZ: 3.6968 (above the threshold of 3.09). GenCC associations: The gene is linked to complex neurodevelopmental disorder, developmental and epileptic encephalopathy, 7, neonatal encephalopathy with non-epileptic myoclonus, benign familial infantile epilepsy, malignant migrating partial seizures of infancy, seizures, benign familial neonatal, 1, benign familial neonatal-infantile seizures, benign neonatal seizures, seizures, benign familial neonatal, 2, undetermined early-onset epileptic encephalopathy, neonatal-onset developmental and epileptic encephalopathy.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.791

BS2

High AC in GnomAdExome4 at 10 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_172107.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
KCNQ2	NM_172107.4	MANE Select	c.1870G>A	p.Gly624Arg	missense	Exon 16 of 17	NP_742105.1	O43526-1
KCNQ2	NM_001382235.1		c.1924G>A	p.Gly642Arg	missense	Exon 16 of 17	NP_001369164.1	A0A9L9PXL0
KCNQ2	NM_172106.3		c.1816G>A	p.Gly606Arg	missense	Exon 15 of 16	NP_742104.1	O43526-2

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
KCNQ2	ENST00000359125.7	TSL:1 MANE Select	c.1870G>A	p.Gly624Arg	missense	Exon 16 of 17	ENSP00000352035.2	O43526-1
KCNQ2	ENST00000626839.2	TSL:1	c.1816G>A	p.Gly606Arg	missense	Exon 15 of 16	ENSP00000486706.1	O43526-2
KCNQ2	ENST00000344462.8	TSL:1	c.1777G>A	p.Gly593Arg	missense	Exon 15 of 16	ENSP00000339611.4	O43526-4

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000125

AC:

AN:

239708

AF XY:

0.00000764

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000293

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000926

Gnomad OTH exome

AF:

0.000170

GnomAD4 exome

AF:

0.00000687

AC:

AN:

1456464

Hom.:

Cov.:

AF XY:

0.00000414

AC XY:

AN XY:

724474

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33420

American (AMR)

AF:

0.0000449

AC:

AN:

44578

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26064

East Asian (EAS)

AF:

0.00

AC:

AN:

39544

South Asian (SAS)

AF:

0.0000117

AC:

AN:

85804

European-Finnish (FIN)

AF:

0.00

AC:

AN:

49966

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5758

European-Non Finnish (NFE)

AF:

0.00000630

AC:

AN:

1111104

Other (OTH)

AF:

0.00

AC:

AN:

60226

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.500

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152190

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74334

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41446

American (AMR)

AF:

0.00

AC:

AN:

15288

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5186

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10626

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68022

Other (OTH)

AF:

0.00

AC:

AN:

2094

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.425

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.0000264

ExAC

AF:

0.00000829

AC:

ClinVar

ClinVar submissions

Significance:Uncertain significance

Revision:criteria provided, multiple submitters, no conflicts

View on ClinVar

Pathogenic

VUS

Benign

Condition

Developmental and epileptic encephalopathy (1)

KCNQ2-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.83

BayesDel_addAF

Uncertain

0.15

BayesDel_noAF

Uncertain

0.080

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.35

Eigen

Uncertain

0.46

Eigen_PC

Uncertain

0.44

FATHMM_MKL

Uncertain

0.94

LIST_S2

Uncertain

0.97

M_CAP

Pathogenic

0.94

MetaRNN

Pathogenic

0.79

MetaSVM

Pathogenic

1.1

MutationAssessor

Uncertain

2.4

PhyloP100

4.7

PrimateAI

Pathogenic

0.82

PROVEAN

Benign

-2.0

REVEL

Pathogenic

0.73

Sift

Benign

0.051

Sift4G

Benign

0.20

Polyphen

1.0

Vest4

0.84

MutPred

0.59

Loss of ubiquitination at K628 (P = 0.0224)

MVP

0.83

MPC

1.8

ClinPred

0.87

GERP RS

4.9

Varity_R

0.78

gMVP

0.92

Mutation Taster

=20/80

disease causing

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.060

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over