rs757596960

chr20-63424191-C-T

Variant summary

Our verdict is Benign. Variant got -15 ACMG points: 0P and 15B. BP4_Moderate BP6_Very_Strong BP7 BS2

The NM_172107.4(KCNQ2):c.1233G>A(p.Pro411=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000148 in 1,555,860 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 0.000013 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000015 (0 hom.)
• Consequence: KCNQ2 NM_172107.4 synonymous
• Clinical Significance: Likely benign criteria provided, multiple submitters, no conflicts B:2
• Conservation: PhyloP100: -0.182

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]

(HGNC:):

ACMG classification

Verdict is Benign. Variant got -15 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.44).
• BP6: Variant 20-63424191-C-T is Benign according to our data. Variant chr20-63424191-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 242007.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BP7: Synonymous conserved (PhyloP=-0.182 with no splicing effect.
• BS2: High AC in GnomAdExome at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNQ2	NM_172107.4	c.1233G>A	p.Pro411=	synonymous_variant	11/17	ENST00000359125.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNQ2	ENST00000359125.7	c.1233G>A	p.Pro411=	synonymous_variant	11/17	1	NM_172107.4	A1
	ENST00000629794.1	n.362-207C>T		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152144 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000307 AC: 5 AN: 162784 Hom.: 0 AF XY: 0.0000466 AC XY: 4 AN XY: 85826

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000804

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: 0.0000471

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000150 AC: 21 AN: 1403716 Hom.: 0 Cov.: 31 AF XY: 0.0000217 AC XY: 15 AN XY: 692640

Gnomad4 AFR exome AF: 0.0000311

Gnomad4 AMR exome AF: 0.0000558

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000148

Gnomad4 OTH exome AF: 0.0000344

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152144 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74306

Gnomad4 AFR AF: 0.0000241

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: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000450 Hom.: 0

Bravo AF: 0.0000227

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Early infantile epileptic encephalopathy with suppression bursts Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Oct 12, 2023

- -

not provided Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Feb 04, 2019

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.44
Cadd	Benign	7.5
Dann	Benign	0.50

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		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

Other links and lift over

dbSNP: rs757596960; hg19: chr20-62055544; COSMIC: COSV60556212; COSMIC: COSV60556212;