20-63407019-G-A

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_172107.4(KCNQ2):​c.2244C>T​(p.His748=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000785 in 1,527,714 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 Likely benign (★★).

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000069 ( 0 hom. )

Consequence

KCNQ2
NM_172107.4 synonymous

Scores

2

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: 0.0250
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 Benign. Variant got -21 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.66).
BP6
Variant 20-63407019-G-A is Benign according to our data. Variant chr20-63407019-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 378031.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=0.025 with no splicing effect.
BS1
Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000164 (25/152220) while in subpopulation AFR AF= 0.000531 (22/41466). AF 95% confidence interval is 0.000359. There are 0 homozygotes in gnomad4. There are 11 alleles in male gnomad4 subpopulation. Median coverage is 34. This position pass quality control queck.
BS2
High AC in GnomAd4 at 25 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
KCNQ2NM_172107.4 linkuse as main transcriptc.2244C>T p.His748= synonymous_variant 17/17 ENST00000359125.7 NP_742105.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
KCNQ2ENST00000359125.7 linkuse as main transcriptc.2244C>T p.His748= synonymous_variant 17/171 NM_172107.4 ENSP00000352035 A1O43526-1

Frequencies

GnomAD3 genomes
AF:
0.000164
AC:
25
AN:
152220
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000531
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000591
AC:
8
AN:
135364
Hom.:
0
AF XY:
0.0000536
AC XY:
4
AN XY:
74606
show subpopulations
Gnomad AFR exome
AF:
0.000538
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:
0.0000741
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000691
AC:
95
AN:
1375494
Hom.:
0
Cov.:
36
AF XY:
0.0000724
AC XY:
49
AN XY:
677194
show subpopulations
Gnomad4 AFR exome
AF:
0.000254
Gnomad4 AMR exome
AF:
0.0000286
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000277
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000755
Gnomad4 OTH exome
AF:
0.0000699
GnomAD4 genome
AF:
0.000164
AC:
25
AN:
152220
Hom.:
0
Cov.:
34
AF XY:
0.000148
AC XY:
11
AN XY:
74358
show subpopulations
Gnomad4 AFR
AF:
0.000531
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000441
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.000238

ClinVar

Significance: Likely benign
Submissions summary: Benign:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:2
Likely benign, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenFeb 01, 2020- -
Likely benign, criteria provided, single submitternot providedBreakthrough Genomics, Breakthrough Genomics-- -
not specified Benign:1
Likely benign, criteria provided, single submitterclinical testingGeneDxNov 09, 2015This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Early infantile epileptic encephalopathy with suppression bursts Benign:1
Likely benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpDec 27, 2023- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.66
CADD
Benign
3.2
DANN
Benign
0.93

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: rs376327268; hg19: chr20-62038372; API