9-135778784-G-A

Position:

chr9-135778784-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.2691G>A(p.Ala897=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000632 in 1,613,736 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.00038 ( 0 hom., cov: 33)

Exomes 𝑓: 0.00066 ( 2 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: -2.27

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=-0.61).

BP6

Variant 9-135778784-G-A is Benign according to our data. Variant chr9-135778784-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 383085.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BP7

Synonymous conserved (PhyloP=-2.27 with no splicing effect.

BS1

Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000381 (58/152286) while in subpopulation SAS AF= 0.000827 (4/4834). AF 95% confidence interval is 0.000495. There are 0 homozygotes in gnomad4. There are 20 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High AC in GnomAd4 at 58 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNT1	NM_020822.3 linkuse as main transcript	c.2691G>A	p.Ala897=	synonymous_variant	23/31	ENST00000371757.7	NP_065873.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNT1	ENST00000371757.7 linkuse as main transcript	c.2691G>A	p.Ala897=	synonymous_variant	23/31	1	NM_020822.3	ENSP00000360822	A2	Q5JUK3-3

Frequencies

GnomAD3 genomes

AF:

0.000368

AC:

AN:

152168

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000966

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.000770

Gnomad SAS

AF:

0.000827

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000647

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000319

AC:

AN:

250948

Hom.:

AF XY:

0.000383

AC XY:

AN XY:

135762

show subpopulations

Gnomad AFR exome

AF:

0.0000616

Gnomad AMR exome

AF:

0.0000579

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00131

Gnomad SAS exome

AF:

0.000457

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000335

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000658

AC:

962

AN:

1461450

Hom.:

Cov.:

AF XY:

0.000641

AC XY:

466

AN XY:

727058

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000157

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.000605

Gnomad4 SAS exome

AF:

0.000557

Gnomad4 FIN exome

AF:

0.0000188

Gnomad4 NFE exome

AF:

0.000721

Gnomad4 OTH exome

AF:

0.00129

GnomAD4 genome

AF:

0.000381

AC:

AN:

152286

Hom.:

Cov.:

AF XY:

0.000269

AC XY:

AN XY:

74462

show subpopulations

Gnomad4 AFR

AF:

0.000144

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.000772

Gnomad4 SAS

AF:

0.000827

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000647

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000458

Hom.:

Bravo

AF:

0.000389

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.000763

EpiControl

AF:

0.000356

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

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

Benign:1

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 24, 2024

- -

Inborn genetic diseases

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 30, 2017

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. -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Oct 11, 2021

- -

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

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

-0.61

CADD

Benign

9.1

DANN

Benign

0.86

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