8-132129662-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_004519.4(KCNQ3):ā€‹c.2219C>Gā€‹(p.Thr740Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,864 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: not found (cov: 33)
Exomes š‘“: 0.0000014 ( 0 hom. )

Consequence

KCNQ3
NM_004519.4 missense

Scores

6
13

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.93
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]

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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;
BP4
Computational evidence support a benign effect (MetaRNN=0.3371063).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
KCNQ3NM_004519.4 linkuse as main transcriptc.2219C>G p.Thr740Arg missense_variant 15/15 ENST00000388996.10 NP_004510.1 O43525-1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
KCNQ3ENST00000388996.10 linkuse as main transcriptc.2219C>G p.Thr740Arg missense_variant 15/151 NM_004519.4 ENSP00000373648.3 O43525-1

Frequencies

GnomAD3 genomes
Cov.:
33
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251218
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135818
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000880
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1461864
Hom.:
0
Cov.:
32
AF XY:
0.00000275
AC XY:
2
AN XY:
727230
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
Cov.:
33
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsAug 28, 2024The c.2219C>G (p.T740R) alteration is located in exon 15 (coding exon 15) of the KCNQ3 gene. This alteration results from a C to G substitution at nucleotide position 2219, causing the threonine (T) at amino acid position 740 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.11
BayesDel_addAF
Uncertain
0.079
D
BayesDel_noAF
Benign
-0.12
CADD
Benign
10
DANN
Benign
0.73
DEOGEN2
Benign
0.34
T;.;.;.;.
Eigen
Benign
-0.64
Eigen_PC
Benign
-0.56
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Uncertain
0.87
D;D;D;D;D
M_CAP
Uncertain
0.089
D
MetaRNN
Benign
0.34
T;T;T;T;T
MetaSVM
Uncertain
0.40
D
MutationAssessor
Benign
0.34
N;.;.;.;.
PrimateAI
Benign
0.32
T
PROVEAN
Benign
-0.78
N;.;N;N;.
REVEL
Uncertain
0.32
Sift
Benign
0.28
T;.;T;T;.
Sift4G
Benign
0.16
T;T;T;T;.
Polyphen
0.17
B;.;.;B;.
Vest4
0.11
MutPred
0.20
Loss of glycosylation at T740 (P = 0.0212);.;.;.;.;
MVP
0.57
MPC
0.18
ClinPred
0.26
T
GERP RS
4.5
Varity_R
0.098
gMVP
0.45

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs764065145; hg19: chr8-133141909; COSMIC: COSV101196343; API