20-63414174-C-G

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 1P and 13B. PP2BP4_StrongBP6BS1BS2

The NM_172107.4(KCNQ2):​c.1545G>C​(p.Glu515Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00116 in 1,613,606 control chromosomes in the GnomAD database, including 36 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely benign in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E515Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0012 ( 6 hom., cov: 32)
Exomes 𝑓: 0.0012 ( 30 hom. )

Consequence

KCNQ2
NM_172107.4 missense

Scores

1
5
12

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:6

Conservation

PhyloP100: 0.157

Publications

21 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: Orphanet, Labcorp Genetics (formerly Invitae), G2P
  • 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
  • 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -12 ACMG points.

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 benign familial infantile epilepsy, malignant migrating partial seizures of infancy, developmental and epileptic encephalopathy, 7, benign familial neonatal-infantile seizures, benign neonatal seizures, neonatal-onset developmental and epileptic encephalopathy, complex neurodevelopmental disorder, seizures, benign familial neonatal, 2, seizures, benign familial neonatal, 1, neonatal encephalopathy with non-epileptic myoclonus.
BP4
Computational evidence support a benign effect (MetaRNN=0.010129333).
BP6
Variant 20-63414174-C-G is Benign according to our data. Variant chr20-63414174-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 21764.We mark this variant Benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].
BS1
Variant frequency is greater than expected in population eas. GnomAd4 allele frequency = 0.00122 (186/152294) while in subpopulation EAS AF = 0.0331 (171/5164). AF 95% confidence interval is 0.0291. There are 6 homozygotes in GnomAd4. There are 94 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High AC in GnomAd4 at 186 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ2NM_172107.4 linkc.1545G>C p.Glu515Asp missense_variant Exon 14 of 17 ENST00000359125.7 NP_742105.1 O43526-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNQ2ENST00000359125.7 linkc.1545G>C p.Glu515Asp missense_variant Exon 14 of 17 1 NM_172107.4 ENSP00000352035.2 O43526-1

Frequencies

GnomAD3 genomes
AF:
0.00120
AC:
183
AN:
152176
Hom.:
6
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000965
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000327
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.0330
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.000479
GnomAD2 exomes
AF:
0.00256
AC:
634
AN:
247908
AF XY:
0.00230
show subpopulations
Gnomad AFR exome
AF:
0.000186
Gnomad AMR exome
AF:
0.000145
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0331
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000905
Gnomad OTH exome
AF:
0.00164
GnomAD4 exome
AF:
0.00115
AC:
1682
AN:
1461312
Hom.:
30
Cov.:
31
AF XY:
0.00106
AC XY:
770
AN XY:
726968
show subpopulations
African (AFR)
AF:
0.0000896
AC:
3
AN:
33476
American (AMR)
AF:
0.000112
AC:
5
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26130
East Asian (EAS)
AF:
0.0375
AC:
1487
AN:
39696
South Asian (SAS)
AF:
0.000243
AC:
21
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53026
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000135
AC:
15
AN:
1111864
Other (OTH)
AF:
0.00250
AC:
151
AN:
60384
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
89
178
267
356
445
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
26
52
78
104
130
<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:
0.00122
AC:
186
AN:
152294
Hom.:
6
Cov.:
32
AF XY:
0.00126
AC XY:
94
AN XY:
74464
show subpopulations
African (AFR)
AF:
0.0000962
AC:
4
AN:
41570
American (AMR)
AF:
0.000327
AC:
5
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.0331
AC:
171
AN:
5164
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68014
Other (OTH)
AF:
0.00190
AC:
4
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.499
Heterozygous variant carriers
0
9
18
28
37
46
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
10
20
30
40
50
<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:
0.000299
Hom.:
0
Bravo
AF:
0.00150
ExAC
AF:
0.00246
AC:
299
Asia WGS
AF:
0.0100
AC:
36
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:6
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:2
Aug 30, 2017
Eurofins Ntd Llc (ga)
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 30, 2021
Genetic Services Laboratory, University of Chicago
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:2
Sep 01, 2020
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 27779742, 32169601, 31180159, 20981092, 22995991, 19380078, 25819767, 28399683, 28038823, 30558019, 31199083) -

Sep 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

KCNQ2: PP2, BS1, BS2 -

Seizures, benign familial neonatal, 1 Uncertain:1
Mar 18, 2016
Soonchunhyang University Bucheon Hospital, Soonchunhyang University Medical Center
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:reference population

- -

Inborn genetic diseases Benign:1
Nov 02, 2016
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

Developmental and epileptic encephalopathy Benign:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Benign
-0.0063
T
BayesDel_noAF
Pathogenic
0.25
CADD
Benign
20
DANN
Uncertain
0.99
DEOGEN2
Benign
0.24
.;.;T;T;T;T;D;T;.;.;T
Eigen
Benign
-0.30
Eigen_PC
Benign
-0.36
FATHMM_MKL
Uncertain
0.86
D
LIST_S2
Benign
0.83
T;T;T;T;T;T;T;T;T;T;T
MetaRNN
Benign
0.010
T;T;T;T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.69
D
MutationAssessor
Benign
1.6
.;.;.;.;.;.;L;.;.;.;.
PhyloP100
0.16
PrimateAI
Uncertain
0.57
T
PROVEAN
Benign
-0.60
.;.;.;.;N;.;N;.;N;.;.
REVEL
Uncertain
0.63
Sift
Benign
0.86
.;.;.;.;T;.;T;.;T;.;.
Sift4G
Benign
0.51
T;T;T;T;T;.;T;T;T;T;T
Polyphen
1.0
D;.;.;.;.;.;D;.;D;P;.
Vest4
0.64
MVP
0.99
MPC
1.6
ClinPred
0.031
T
GERP RS
1.2
Varity_R
0.12
gMVP
0.58
Mutation Taster
=21/79
disease causing

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

Other links and lift over

dbSNP: rs117067974; hg19: chr20-62045527; COSMIC: COSV107413946; COSMIC: COSV107413946; API