rs914428

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BA1

The NM_020822.3(KCNT1):​c.2427G>A​(p.Thr809Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.676 in 1,613,708 control chromosomes in the GnomAD database, including 372,007 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★).

Frequency

Genomes: 𝑓 0.65 ( 32274 hom., cov: 33)
Exomes 𝑓: 0.68 ( 339733 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

2

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:13

Conservation

PhyloP100: -3.94
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]

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=-0.6).
BP6
Variant 9-135777415-G-A is Benign according to our data. Variant chr9-135777415-G-A is described in ClinVar as [Benign]. Clinvar id is 129357.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-135777415-G-A is described in Lovd as [Benign].
BP7
Synonymous conserved (PhyloP=-3.94 with no splicing effect.
BA1
GnomAd4 highest subpopulation (SAS) allele frequency at 95% confidence interval = 0.73 is higher than 0.05.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNT1NM_020822.3 linkc.2427G>A p.Thr809Thr synonymous_variant Exon 21 of 31 ENST00000371757.7 NP_065873.2 Q5JUK3-3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNT1ENST00000371757.7 linkc.2427G>A p.Thr809Thr synonymous_variant Exon 21 of 31 1 NM_020822.3 ENSP00000360822.2 Q5JUK3-3

Frequencies

GnomAD3 genomes
AF:
0.647
AC:
98304
AN:
151916
Hom.:
32246
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.567
Gnomad AMI
AF:
0.796
Gnomad AMR
AF:
0.663
Gnomad ASJ
AF:
0.488
Gnomad EAS
AF:
0.588
Gnomad SAS
AF:
0.751
Gnomad FIN
AF:
0.766
Gnomad MID
AF:
0.427
Gnomad NFE
AF:
0.679
Gnomad OTH
AF:
0.613
GnomAD3 exomes
AF:
0.668
AC:
167817
AN:
251278
Hom.:
56838
AF XY:
0.671
AC XY:
91156
AN XY:
135828
show subpopulations
Gnomad AFR exome
AF:
0.557
Gnomad AMR exome
AF:
0.659
Gnomad ASJ exome
AF:
0.496
Gnomad EAS exome
AF:
0.592
Gnomad SAS exome
AF:
0.748
Gnomad FIN exome
AF:
0.764
Gnomad NFE exome
AF:
0.675
Gnomad OTH exome
AF:
0.645
GnomAD4 exome
AF:
0.679
AC:
993200
AN:
1461674
Hom.:
339733
Cov.:
53
AF XY:
0.681
AC XY:
495342
AN XY:
727164
show subpopulations
Gnomad4 AFR exome
AF:
0.562
Gnomad4 AMR exome
AF:
0.658
Gnomad4 ASJ exome
AF:
0.491
Gnomad4 EAS exome
AF:
0.576
Gnomad4 SAS exome
AF:
0.738
Gnomad4 FIN exome
AF:
0.766
Gnomad4 NFE exome
AF:
0.686
Gnomad4 OTH exome
AF:
0.652
GnomAD4 genome
AF:
0.647
AC:
98378
AN:
152034
Hom.:
32274
Cov.:
33
AF XY:
0.651
AC XY:
48364
AN XY:
74314
show subpopulations
Gnomad4 AFR
AF:
0.567
Gnomad4 AMR
AF:
0.663
Gnomad4 ASJ
AF:
0.488
Gnomad4 EAS
AF:
0.588
Gnomad4 SAS
AF:
0.751
Gnomad4 FIN
AF:
0.766
Gnomad4 NFE
AF:
0.679
Gnomad4 OTH
AF:
0.616
Alfa
AF:
0.658
Hom.:
55834
Bravo
AF:
0.630
Asia WGS
AF:
0.667
AC:
2320
AN:
3478
EpiCase
AF:
0.659
EpiControl
AF:
0.642

ClinVar

Significance: Benign
Submissions summary: Benign:13
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:7
-
Genetic Services Laboratory, University of Chicago
Significance: Likely benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

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. -

-
PreventionGenetics, part of Exact Sciences
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jul 15, 2024
Unidad de Genómica Garrahan, Hospital de Pediatría Garrahan
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is classified as Benign based on local population frequency. This variant was detected in 88% of patients studied in a panel designed for Epileptic and Developmental Encephalopathy and Progressive Myoclonus Epilepsy. Number of patients: 82. Only high quality variants are reported. -

-
Clinical Genetics, Academic Medical Center
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Jan 04, 2016
GeneDx
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

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. -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance: Benign
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not provided Benign:2
May 06, 2018
Athena Diagnostics
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

-
Breakthrough Genomics, Breakthrough Genomics
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: not provided

- -

Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Feb 04, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Inborn genetic diseases Benign:1
Dec 31, 2015
Ambry Genetics
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

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. -

Developmental and epileptic encephalopathy, 14 Benign:1
Aug 19, 2021
Genome-Nilou Lab
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1
Aug 19, 2021
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
-0.60
CADD
Benign
1.0
DANN
Benign
0.84

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: rs914428; hg19: chr9-138669261; COSMIC: COSV53696861; COSMIC: COSV53696861; API