rs115092422

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_004519.4(KCNQ3):c.1700+3G>A variant causes a splice donor region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00242 in 1,613,984 control chromosomes in the GnomAD database, including 87 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.013 ( 51 hom., cov: 32)

Exomes 𝑓: 0.0013 ( 36 hom. )

Consequence

KCNQ3
NM_004519.4 splice_donor_region, intron

Scores

Splicing: ADA: 0.00002082

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:7

Conservation

PhyloP100: 0.536

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -20 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.8).

BP6

Variant 8-132137882-C-T is Benign according to our data. Variant chr8-132137882-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 361879.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr8-132137882-C-T is described in Lovd as [Likely_benign].

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.013 (1985/152290) while in subpopulation AFR AF= 0.0455 (1889/41552). AF 95% confidence interval is 0.0438. There are 51 homozygotes in gnomad4. There are 910 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

BS2

High AC in GnomAd at 1980 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ3	NM_004519.4 linkuse as main transcript	c.1700+3G>A		splice_donor_region_variant, intron_variant		ENST00000388996.10

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ3	ENST00000388996.10 linkuse as main transcript	c.1700+3G>A		splice_donor_region_variant, intron_variant		1	NM_004519.4	P1	O43525-1

Frequencies

GnomAD3 genomes

AF:

0.0130

AC:

1980

AN:

152172

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0455

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00425

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00316

Gnomad NFE

AF:

0.000103

Gnomad OTH

AF:

0.0105

GnomAD3 exomes

AF:

0.00328

AC:

825

AN:

251292

Hom.:

AF XY:

0.00247

AC XY:

336

AN XY:

135822

show subpopulations

Gnomad AFR exome

AF:

0.0452

Gnomad AMR exome

AF:

0.00173

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000229

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000114

Gnomad OTH exome

AF:

0.00163

GnomAD4 exome

AF:

0.00131

AC:

1917

AN:

1461694

Hom.:

Cov.:

AF XY:

0.00113

AC XY:

822

AN XY:

727162

show subpopulations

Gnomad4 AFR exome

AF:

0.0453

Gnomad4 AMR exome

AF:

0.00235

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000139

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000567

Gnomad4 OTH exome

AF:

0.00339

GnomAD4 genome

AF:

0.0130

AC:

1985

AN:

152290

Hom.:

Cov.:

AF XY:

0.0122

AC XY:

910

AN XY:

74466

show subpopulations

Gnomad4 AFR

AF:

0.0455

Gnomad4 AMR

AF:

0.00425

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000103

Gnomad4 OTH

AF:

0.0104

Alfa

AF:

0.00637

Hom.:

Bravo

AF:

0.0144

Asia WGS

AF:

0.00289

AC:

AN:

3478

EpiCase

AF:

0.000109

EpiControl

AF:

0.000178

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Benign neonatal seizures

Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jun 14, 2016	- -
Benign, criteria provided, single submitter	clinical testing	Invitae	Feb 01, 2024	- -

Seizures, benign familial neonatal, 2

Benign:2

Benign, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Oct 07, 2021	- -
Benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jan 12, 2018	This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

not provided

Benign:2

Benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 03, 2015	- -
Benign, criteria provided, single submitter	clinical testing	Center for Pediatric Genomic Medicine, Children's Mercy Hospital and Clinics	May 30, 2017	- -

Inborn genetic diseases

Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Jan 08, 2016

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.80

Cadd

Benign

2.5

Dann

Benign

0.50

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.000021

dbscSNV1_RF

Benign

0.012

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over