rs143016981

Variant summary

Our verdict is Benign. The variant received -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_172107.4(KCNQ2):​c.2385C>T​(p.His795His) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000206 in 1,612,038 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 (★★).

Frequency

Genomes: 𝑓 0.00015 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00021 ( 0 hom. )

Consequence

KCNQ2
NM_172107.4 synonymous

Scores

2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: -0.327

Publications

2 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 -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.51).
BP6
Variant 20-63406878-G-A is Benign according to our data. Variant chr20-63406878-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 138031.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=-0.327 with no splicing effect.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.000151 (23/152368) while in subpopulation NFE AF = 0.000235 (16/68020). AF 95% confidence interval is 0.000147. There are 0 homozygotes in GnomAd4. There are 9 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check.
BS2
High AC in GnomAd4 at 23 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ2NM_172107.4 linkc.2385C>T p.His795His synonymous_variant Exon 17 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.2385C>T p.His795His synonymous_variant Exon 17 of 17 1 NM_172107.4 ENSP00000352035.2 O43526-1

Frequencies

GnomAD3 genomes
AF:
0.000151
AC:
23
AN:
152250
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000965
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.000235
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000101
AC:
25
AN:
246458
AF XY:
0.000104
show subpopulations
Gnomad AFR exome
AF:
0.000190
Gnomad AMR exome
AF:
0.0000291
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000547
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000162
Gnomad OTH exome
AF:
0.000166
GnomAD4 exome
AF:
0.000212
AC:
309
AN:
1459670
Hom.:
0
Cov.:
30
AF XY:
0.000208
AC XY:
151
AN XY:
726042
show subpopulations
African (AFR)
AF:
0.0000598
AC:
2
AN:
33468
American (AMR)
AF:
0.0000448
AC:
2
AN:
44670
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26094
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39672
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86120
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51900
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000268
AC:
298
AN:
1111650
Other (OTH)
AF:
0.0000829
AC:
5
AN:
60328
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.488
Heterozygous variant carriers
0
19
38
57
76
95
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<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:
0.000151
AC:
23
AN:
152368
Hom.:
0
Cov.:
33
AF XY:
0.000121
AC XY:
9
AN XY:
74508
show subpopulations
African (AFR)
AF:
0.0000962
AC:
4
AN:
41590
American (AMR)
AF:
0.000131
AC:
2
AN:
15310
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5194
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000235
AC:
16
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2114
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.499
Heterozygous variant carriers
0
2
4
5
7
9
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<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:
0.000158
Hom.:
0
Bravo
AF:
0.000155
EpiCase
AF:
0.000327
EpiControl
AF:
0.00

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:1
Jun 03, 2014
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

KCNQ2-related disorder Benign:1
Mar 15, 2019
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Inborn genetic diseases Benign:1
Aug 14, 2017
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. -

Developmental and epileptic encephalopathy Benign:1
Jan 11, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:1
Sep 01, 2022
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

KCNQ2: BP4, BP7 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.51
CADD
Benign
5.2
DANN
Benign
0.71
PhyloP100
-0.33
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

Publications

Other links and lift over

dbSNP: rs143016981; hg19: chr20-62038231; API