rs1057516116

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2PP2BP4_Moderate

The NM_172107.4(KCNQ2):​c.1382A>C​(p.Gln461Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,142 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Consequence

KCNQ2
NM_172107.4 missense

Scores

7
12

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2O:1

Conservation

PhyloP100: 0.944
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
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 seizures, benign familial neonatal, 1, neonatal-onset developmental and epileptic encephalopathy, benign familial neonatal-infantile seizures, benign neonatal seizures, malignant migrating partial seizures of infancy, neonatal encephalopathy with non-epileptic myoclonus, complex neurodevelopmental disorder, seizures, benign familial neonatal, 2, developmental and epileptic encephalopathy, 7, benign familial infantile epilepsy.
BP4
Computational evidence support a benign effect (MetaRNN=0.18376032).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ2NM_172107.4 linkc.1382A>C p.Gln461Pro missense_variant Exon 13 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.1382A>C p.Gln461Pro missense_variant Exon 13 of 17 1 NM_172107.4 ENSP00000352035.2 O43526-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152142
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
Cov.:
35
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152142
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74316
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.0000654
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 7 Uncertain:1Other:1
Feb 02, 2022
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3B. Following criteria are met: 0103 - Dominant negative and loss of function are known mechanisms of disease in this gene and are associated with early infantile epileptic encephalopathy, 7 (EIEE) (MIM#613720) and benign neonatal seizures, 1 (BNS) (MIM#121200). Missense variants have been reported with a dominant negative mechanism (OMIM, PMID 24318194) and in patients with either condition. Truncating variants and those predicted to undergo nonsense-mediated decay, have been reported to cause loss of function (DECIPHER) and are almost exclusively found in patients with BNS (PMID: 32917465). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0112 - The condition associated with this gene has incomplete penetrance, however, this is only reported for patients with BNS (PMID 25959266). (I) 0200 - Variant is predicted to result in a missense amino acid change from glutamine to proline. (I) 0251 - This variant is heterozygous. (I) 0302 - Variant is present in gnomAD (v3) <0.001 for a dominant condition (1 heterozygote, 0 homozygotes). (SP) 0504 - Same amino acid change has been observed in placental mammals. (SB) 0604 - Variant is not located in an established domain, motif, hotspot or informative constraint region. (I) 0710 - Another missense variant comparable to the one identified in this case has inconclusive previous evidence for pathogenicity. The p.(Gln461His) has been reported a VUS in ClinVar. (I) 0809 - Previous evidence of pathogenicity for this variant is inconclusive. This variant has been previously described as pathogenic in ClinVar referring to a patient with epileptic encephalopathy (PMID: 23708187), however subsequent testing of this patient's unaffected mother identified the variant and it was re-classified to likely non-pathogenic (The RIKEE Project). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

-
GeneReviews
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

EE (epileptic encephalopathy) -

Early infantile epileptic encephalopathy with suppression bursts Uncertain:1
Sep 06, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Benign"; Align-GVGD: "Not Available". The proline amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. ClinVar contains an entry for this variant (Variation ID: 369794). This missense change has been observed in individual(s) with clinical features of KCNQ2-related conditions (PMID: 23708187). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamine, which is neutral and polar, with proline, which is neutral and non-polar, at codon 461 of the KCNQ2 protein (p.Gln461Pro). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.048
BayesDel_addAF
Uncertain
0.14
D
BayesDel_noAF
Uncertain
-0.030
CADD
Benign
20
DANN
Benign
0.96
DEOGEN2
Benign
0.28
.;.;T;T;T;T;T;T;.;.
Eigen
Benign
-0.55
Eigen_PC
Benign
-0.35
FATHMM_MKL
Uncertain
0.83
D
LIST_S2
Benign
0.84
T;T;T;T;T;T;T;T;T;T
M_CAP
Uncertain
0.14
D
MetaRNN
Benign
0.18
T;T;T;T;T;T;T;T;T;T
MetaSVM
Uncertain
0.32
D
MutationAssessor
Benign
0.80
.;.;.;.;.;.;N;.;.;.
PrimateAI
Uncertain
0.73
T
PROVEAN
Benign
-0.69
.;.;.;.;N;.;N;.;N;N
REVEL
Uncertain
0.47
Sift
Benign
0.13
.;.;.;.;T;.;T;.;T;T
Sift4G
Benign
0.33
T;T;T;T;T;.;T;T;T;T
Polyphen
0.0020
B;.;.;.;.;.;B;.;B;B
Vest4
0.38
MutPred
0.14
.;.;.;.;.;.;Loss of MoRF binding (P = 0.0407);.;.;.;
MVP
0.79
MPC
0.77
ClinPred
0.18
T
GERP RS
2.8
Varity_R
0.16
gMVP
0.46

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs1057516116; hg19: chr20-62046399; API