8-132141191-T-C

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS1

The NM_004519.4(KCNQ3):​c.1403A>G​(p.Asn468Ser) variant causes a missense change. The variant allele was found at a frequency of 0.0000545 in 1,614,220 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N468K) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000055 ( 0 hom. )

Consequence

KCNQ3
NM_004519.4 missense

Scores

2
5
12

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:4O:1

Conservation

PhyloP100: 3.93

Publications

8 publications found
Variant links:
Genes affected
KCNQ3 (HGNC:6297): (potassium voltage-gated channel subfamily Q member 3) This gene encodes a protein that functions in the regulation of neuronal excitability. The encoded protein forms an M-channel by associating with the products of the related KCNQ2 or KCNQ5 genes, which both encode integral membrane proteins. M-channel currents are inhibited by M1 muscarinic acetylcholine receptors and are activated by retigabine, a novel anti-convulsant drug. Defects in this gene are a cause of benign familial neonatal convulsions type 2 (BFNC2), also known as epilepsy, benign neonatal type 2 (EBN2). Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2014]
KCNQ3 Gene-Disease associations (from GenCC):
  • seizures, benign familial neonatal, 2
    Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • benign familial infantile epilepsy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • benign neonatal seizures
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • genetic developmental and epileptic encephalopathy
    Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.072870016).
BP6
Variant 8-132141191-T-C is Benign according to our data. Variant chr8-132141191-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 21410.
BS1
Variant frequency is greater than expected in population sas. GnomAdExome4 allele frequency = 0.0000547 (80/1461884) while in subpopulation SAS AF = 0.000672 (58/86258). AF 95% confidence interval is 0.000533. There are 0 homozygotes in GnomAdExome4. There are 54 alleles in the male GnomAdExome4 subpopulation. Median coverage is 31. This position passed quality control check.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ3NM_004519.4 linkc.1403A>G p.Asn468Ser missense_variant Exon 10 of 15 ENST00000388996.10 NP_004510.1 O43525-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNQ3ENST00000388996.10 linkc.1403A>G p.Asn468Ser missense_variant Exon 10 of 15 1 NM_004519.4 ENSP00000373648.3 O43525-1

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152218
Hom.:
0
Cov.:
32
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:
0.000771
Gnomad SAS
AF:
0.000620
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000151
AC:
38
AN:
251480
AF XY:
0.000177
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000652
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000547
AC:
80
AN:
1461884
Hom.:
0
Cov.:
31
AF XY:
0.0000743
AC XY:
54
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.000302
AC:
12
AN:
39700
South Asian (SAS)
AF:
0.000672
AC:
58
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1112002
Other (OTH)
AF:
0.000149
AC:
9
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.501
Heterozygous variant carriers
0
7
13
20
26
33
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000525
AC:
8
AN:
152336
Hom.:
0
Cov.:
32
AF XY:
0.0000805
AC XY:
6
AN XY:
74500
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41570
American (AMR)
AF:
0.00
AC:
0
AN:
15308
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.000773
AC:
4
AN:
5176
South Asian (SAS)
AF:
0.000621
AC:
3
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10628
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.494
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000106
Hom.:
0
Bravo
AF:
0.0000491
ExAC
AF:
0.000123
AC:
15
Asia WGS
AF:
0.00115
AC:
4
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:4Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1Benign:2
Jun 03, 2014
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 08, 2019
Athena Diagnostics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jul 25, 2019
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant is associated with the following publications: (PMID: 14534157, 32613771) -

Inborn genetic diseases Benign:1
Jan 28, 2025
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. -

Benign neonatal seizures Benign:1
Nov 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Seizures, benign familial neonatal, 2 Other:1
-
GeneReviews
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

All 3 sibs with the variant were affected. Chinese ethnicity; variant is present in 0.06% of East Asians (gnomAD) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.071
BayesDel_addAF
Benign
-0.21
T
BayesDel_noAF
Benign
-0.16
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.75
D;.;.;.;.
Eigen
Benign
-0.098
Eigen_PC
Benign
0.060
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.88
D;D;D;D;D
M_CAP
Benign
0.051
D
MetaRNN
Benign
0.073
T;T;T;T;T
MetaSVM
Pathogenic
1.2
D
MutationAssessor
Benign
1.9
L;.;.;.;.
PhyloP100
3.9
PrimateAI
Uncertain
0.58
T
PROVEAN
Benign
-1.4
N;.;N;N;.
REVEL
Uncertain
0.47
Sift
Benign
0.15
T;.;T;T;.
Sift4G
Benign
0.16
T;T;T;T;.
Polyphen
0.051
B;.;.;B;.
Vest4
0.32
MVP
0.83
MPC
0.82
ClinPred
0.080
T
GERP RS
4.4
Varity_R
0.15
gMVP
0.45
Mutation Taster
=70/30
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: rs118192252; hg19: chr8-133153438; API