rs374347802

Variant names:

Variant summary

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

The NM_020822.3(KCNT1):c.2166G>A(p.Leu722Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000553 in 1,556,888 control chromosomes in the GnomAD database, including 4 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00033 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00058 ( 4 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8

Conservation

PhyloP100: 0.663

Variant links:

Genes affected

KCNT1 (HGNC:18865): (potassium sodium-activated channel subfamily T member 1) Potassium channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. This gene encodes a sodium-activated potassium channel subunit which is thought to function in ion conductance and developmental signaling pathways. Mutations in this gene cause the early-onset epileptic disorders, malignant migrating partial seizures of infancy and autosomal dominant nocturnal frontal lobe epilepsy. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2012]

KCNT1 links:

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=-0.53).

BP6

Variant 9-135772872-G-A is Benign according to our data. Variant chr9-135772872-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 385228.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-135772872-G-A is described in Lovd as [Likely_benign].

BP7

Synonymous conserved (PhyloP=0.663 with no splicing effect.

BS1

Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000335 (51/152346) while in subpopulation SAS AF= 0.00187 (9/4820). AF 95% confidence interval is 0.000974. There are 0 homozygotes in gnomad4. There are 26 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High AC in GnomAd4 at 51 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNT1	NM_020822.3 link	c.2166G>A	p.Leu722Leu	synonymous_variant	Exon 19 of 31	ENST00000371757.7	NP_065873.2	Q5JUK3-3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNT1	ENST00000371757.7 link	c.2166G>A	p.Leu722Leu	synonymous_variant	Exon 19 of 31	1	NM_020822.3	ENSP00000360822.2		Q5JUK3-3

Frequencies

GnomAD3 genomes

AF:

0.000335

AC:

AN:

152228

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000193

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00187

Gnomad FIN

AF:

0.0000941

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000470

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000550

AC:

AN:

163616

Hom.:

AF XY:

0.000566

AC XY:

AN XY:

88272

show subpopulations

Gnomad AFR exome

AF:

0.0000991

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.0000803

Gnomad SAS exome

AF:

0.00192

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000630

Gnomad OTH exome

AF:

0.000448

GnomAD4 exome

AF:

0.000577

AC:

810

AN:

1404542

Hom.:

Cov.:

AF XY:

0.000621

AC XY:

431

AN XY:

693990

show subpopulations

Gnomad4 AFR exome

AF:

0.0000623

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.0000399

Gnomad4 EAS exome

AF:

0.0000273

Gnomad4 SAS exome

AF:

0.00199

Gnomad4 FIN exome

AF:

0.000105

Gnomad4 NFE exome

AF:

0.000547

Gnomad4 OTH exome

AF:

0.000688

GnomAD4 genome

AF:

0.000335

AC:

AN:

152346

Hom.:

Cov.:

AF XY:

0.000349

AC XY:

AN XY:

74494

show subpopulations

Gnomad4 AFR

AF:

0.000192

Gnomad4 AMR

AF:

0.0000653

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00187

Gnomad4 FIN

AF:

0.0000941

Gnomad4 NFE

AF:

0.000470

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000448

Hom.:

Bravo

AF:

0.000310

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:8

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not provided

Benign:4

Nov 02, 2020

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Mar 19, 2018

Athena Diagnostics

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Genome Diagnostics Laboratory, University Medical Center Utrecht

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5

Benign:1

Jan 27, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Inborn genetic diseases

Benign:1

Oct 12, 2017

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely 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. -

Developmental and epileptic encephalopathy, 14

Benign:1

Mar 15, 2022

Genome-Nilou Lab

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Autosomal dominant nocturnal frontal lobe epilepsy 5

Benign:1

Mar 15, 2022

Genome-Nilou Lab

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.53

CADD

Benign

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.

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