rs397514581

Variant summary

Our verdict is Pathogenic. The variant received 19 ACMG points: 19P and 0B. PM1PM2PM5PP2PP3_StrongPP5_Very_Strong

The NM_172107.4(KCNQ2):​c.638G>T​(p.Arg213Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R213Q) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 33)
Exomes 𝑓: 0.0 ( 0 hom. )
Failed GnomAD Quality Control

Consequence

KCNQ2
NM_172107.4 missense

Scores

12
5
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 7.74

Publications

0 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: Pathogenic. The variant received 19 ACMG points.

PM1
In a hotspot region, there are 30 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_172107.4
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr20-63444711-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 39760.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
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.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.989
PP5
Variant 20-63444711-C-A is Pathogenic according to our data. Variant chr20-63444711-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 1685899.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNQ2NM_172107.4 linkc.638G>T p.Arg213Leu missense_variant Exon 4 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.638G>T p.Arg213Leu missense_variant Exon 4 of 17 1 NM_172107.4 ENSP00000352035.2 O43526-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD4 exome
Data not reliable, filtered out with message: AC0
AF:
0.00
AC:
0
AN:
1442490
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
715340
African (AFR)
AF:
0.00
AC:
0
AN:
33298
American (AMR)
AF:
0.00
AC:
0
AN:
41688
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25718
East Asian (EAS)
AF:
0.00
AC:
0
AN:
38962
South Asian (SAS)
AF:
0.00
AC:
0
AN:
83350
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50898
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5736
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1103152
Other (OTH)
AF:
0.00
AC:
0
AN:
59688
GnomAD4 genome
Cov.:
33

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy Pathogenic:1
Jan 11, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with leucine, which is neutral and non-polar, at codon 213 of the KCNQ2 protein (p.Arg213Leu). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with KCNQ2-related conditions. ClinVar contains an entry for this variant (Variation ID: 1685899). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt KCNQ2 protein function with a positive predictive value of 95%. This variant disrupts the p.Arg213 amino acid residue in KCNQ2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 18353052, 23440208, 27779742, 29056246). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Seizures, benign familial neonatal, 1 Pathogenic:1
May 04, 2022
Mendelics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.57
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
31
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.57
.;.;D;D;D;T;D;D;.;.;.;.
Eigen
Uncertain
0.68
Eigen_PC
Uncertain
0.55
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Pathogenic
0.99
D;D;D;D;D;D;D;D;D;D;D;D
M_CAP
Pathogenic
0.93
D
MetaRNN
Pathogenic
0.99
D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
4.1
H;.;.;.;.;.;H;.;H;H;H;.
PhyloP100
7.7
PrimateAI
Pathogenic
0.92
D
PROVEAN
Pathogenic
-6.3
.;.;.;.;D;.;D;.;D;D;D;.
REVEL
Pathogenic
0.91
Sift
Pathogenic
0.0
.;.;.;.;D;.;D;.;D;D;D;.
Sift4G
Benign
0.063
T;D;T;T;T;.;T;T;T;T;D;T
Polyphen
1.0
D;.;.;.;.;.;D;.;D;D;.;.
Vest4
0.96
MutPred
0.91
Loss of solvent accessibility (P = 0.0606);Loss of solvent accessibility (P = 0.0606);Loss of solvent accessibility (P = 0.0606);Loss of solvent accessibility (P = 0.0606);Loss of solvent accessibility (P = 0.0606);.;Loss of solvent accessibility (P = 0.0606);.;Loss of solvent accessibility (P = 0.0606);Loss of solvent accessibility (P = 0.0606);Loss of solvent accessibility (P = 0.0606);.;
MVP
0.99
MPC
3.1
ClinPred
1.0
D
GERP RS
4.0
PromoterAI
0.016
Neutral
Varity_R
0.93
gMVP
0.99
Mutation Taster
=0/100
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: rs397514581; hg19: chr20-62076064; API