rs185628977

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_StrongBP6

The NM_004519.4(KCNQ3):​c.2491C>T​(p.Arg831Trp) variant causes a missense change. The variant allele was found at a frequency of 0.000018 in 1,614,170 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. R831Q) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

KCNQ3
NM_004519.4 missense

Scores

9
10

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:2

Conservation

PhyloP100: 3.65

Publications

1 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: Likely_benign. The variant received -5 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.06149566).
BP6
Variant 8-132129390-G-A is Benign according to our data. Variant chr8-132129390-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 205954.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ3NM_004519.4 linkc.2491C>T p.Arg831Trp missense_variant Exon 15 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.2491C>T p.Arg831Trp missense_variant Exon 15 of 15 1 NM_004519.4 ENSP00000373648.3 O43525-1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152164
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000262
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000597
AC:
15
AN:
251400
AF XY:
0.0000589
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000376
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.0000157
AC:
23
AN:
1461888
Hom.:
0
Cov.:
32
AF XY:
0.0000179
AC XY:
13
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000335
AC:
15
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1112008
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
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

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:
0.0000394
AC:
6
AN:
152282
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74470
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41566
American (AMR)
AF:
0.000261
AC:
4
AN:
15300
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5170
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2110
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.517
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:
0.0000187
Hom.:
0
Bravo
AF:
0.0000529
ExAC
AF:
0.0000741
AC:
9
Asia WGS
AF:
0.000289
AC:
1
AN:
3478

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Uncertain:1
Jul 19, 2017
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Feb 28, 2017
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R831W variant (also known as c.2491C>T), located in coding exon 15 of the KCNQ3 gene, results from a C to T substitution at nucleotide position 2491. The arginine at codon 831 is replaced by tryptophan, an amino acid with dissimilar properties. This variant did not co-segregate with disease in three individuals tested in our laboratory. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Benign neonatal seizures Benign:1
Oct 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:1
Apr 30, 2019
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
BayesDel_addAF
Benign
-0.22
T
BayesDel_noAF
Benign
-0.24
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.43
T;.;.;.
Eigen
Uncertain
0.20
Eigen_PC
Benign
0.19
FATHMM_MKL
Uncertain
0.94
D
LIST_S2
Uncertain
0.95
D;D;D;D
M_CAP
Benign
0.043
D
MetaRNN
Benign
0.061
T;T;T;T
MetaSVM
Benign
-0.68
T
MutationAssessor
Benign
1.2
L;.;.;.
PhyloP100
3.7
PrimateAI
Uncertain
0.67
T
PROVEAN
Benign
-1.9
N;.;N;N
REVEL
Uncertain
0.32
Sift
Uncertain
0.016
D;.;D;D
Sift4G
Uncertain
0.041
D;D;D;D
Polyphen
1.0
D;.;.;D
Vest4
0.38
MVP
0.37
MPC
0.51
ClinPred
0.24
T
GERP RS
2.6
Varity_R
0.089
gMVP
0.23
Mutation Taster
=54/46
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: rs185628977; hg19: chr8-133141637; COSMIC: COSV101196216; COSMIC: COSV101196216; API