rs149416418

Positions:

chr9-135786331-G-A

Variant summary

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

The NM_020822.3(KCNT1):c.3312G>A(p.Leu1104Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00125 in 1,596,228 control chromosomes in the GnomAD database, including 25 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.0062 ( 12 hom., cov: 33)

Exomes 𝑓: 0.00072 ( 13 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:10

Conservation

PhyloP100: 0.427

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:

KCNT1 (HGNC:):

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=-0.56).

BP6

Variant 9-135786331-G-A is Benign according to our data. Variant chr9-135786331-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 129363.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-135786331-G-A is described in Lovd as [Likely_benign].

BP7

Synonymous conserved (PhyloP=0.427 with no splicing effect.

BS1

Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00619 (943/152250) while in subpopulation AFR AF= 0.0212 (882/41560). AF 95% confidence interval is 0.0201. There are 12 homozygotes in gnomad4. There are 431 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High AC in GnomAd4 at 943 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNT1	NM_020822.3 linkuse as main transcript	c.3312G>A	p.Leu1104Leu	synonymous_variant	29/31	ENST00000371757.7	NP_065873.2	Q5JUK3-3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNT1	ENST00000371757.7 linkuse as main transcript	c.3312G>A	p.Leu1104Leu	synonymous_variant	29/31	1	NM_020822.3	ENSP00000360822.2		Q5JUK3-3

Frequencies

GnomAD3 genomes

AF:

0.00612

AC:

931

AN:

152134

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0210

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00301

Gnomad ASJ

AF:

0.000576

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000118

Gnomad OTH

AF:

0.00239

GnomAD3 exomes

AF:

0.00148

AC:

299

AN:

202530

Hom.:

AF XY:

0.00102

AC XY:

114

AN XY:

111930

show subpopulations

Gnomad AFR exome

AF:

0.0222

Gnomad AMR exome

AF:

0.00131

Gnomad ASJ exome

AF:

0.000674

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000361

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000105

Gnomad OTH exome

AF:

0.000972

GnomAD4 exome

AF:

0.000724

AC:

1046

AN:

1443978

Hom.:

Cov.:

AF XY:

0.000601

AC XY:

431

AN XY:

716702

show subpopulations

Gnomad4 AFR exome

AF:

0.0236

Gnomad4 AMR exome

AF:

0.00155

Gnomad4 ASJ exome

AF:

0.000897

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000713

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000534

Gnomad4 OTH exome

AF:

0.00179

GnomAD4 genome

AF:

0.00619

AC:

943

AN:

152250

Hom.:

Cov.:

AF XY:

0.00579

AC XY:

431

AN XY:

74434

show subpopulations

Gnomad4 AFR

AF:

0.0212

Gnomad4 AMR

AF:

0.00301

Gnomad4 ASJ

AF:

0.000576

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000118

Gnomad4 OTH

AF:

0.00237

Alfa

AF:

0.00202

Hom.:

Bravo

AF:

0.00744

Asia WGS

AF:

0.00202

AC:

AN:

3476

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:10

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Benign:3

Benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Apr 21, 2015	- -
Likely benign, no assertion criteria provided	clinical testing	Genetic Services Laboratory, University of Chicago	-	Likely benign based on allele frequency in 1000 Genomes Project or ESP global frequency and its presence in a patient with a rare or unrelated disease phenotype. NOT Sanger confirmed. -
Benign, criteria provided, single submitter	clinical testing	GeneDx	Feb 18, 2016	This 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. -

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

Benign:2

Likely benign, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	Jan 24, 2022	- -
Benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Feb 01, 2024	- -

Inborn genetic diseases

Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 11, 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. -

KCNT1-related disorder

Benign:1

Benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

May 28, 2019

This variant is classified as benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

not provided

Benign:1

Benign, criteria provided, single submitter

not provided

Breakthrough Genomics, Breakthrough Genomics

- -

Developmental and epileptic encephalopathy, 14

Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Mar 15, 2022

- -

Autosomal dominant nocturnal frontal lobe epilepsy 5

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Mar 15, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.56

CADD

Benign

0.33

DANN

Benign

0.70

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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