Genetic Variant KCNT1:c.601-13C>T (chr9-135757143-C-T) – ACMG Classification: Benign (-16 pts)

Variant summary

Our verdict is Benign. Variant got -16 ACMG points: 0P and 16B. BP4_StrongBP6_Very_StrongBS2

The NM_020822.3(KCNT1):c.601-13C>T variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000436 in 1,607,014 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 0.000040 ( 0 hom., cov: 24)

Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 intron

Scores

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: 0.0930

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:

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ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -16 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.87).

BP6

Variant 9-135757143-C-T is Benign according to our data. Variant chr9-135757143-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 385389.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS2

High AC in GnomAd4 at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNT1	NM_020822.3 link	c.601-13C>T		intron_variant	Intron 7 of 30	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.601-13C>T		intron_variant	Intron 7 of 30	1	NM_020822.3	ENSP00000360822.2		Q5JUK3-3

Frequencies

GnomAD3 genomes

AF:

0.0000398

AC:

AN:

150654

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000662

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:

0.0000739

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000121

AC:

AN:

248202

Hom.:

AF XY:

0.00000742

AC XY:

AN XY:

134734

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

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:

0.0000177

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000439

AC:

AN:

1456360

Hom.:

Cov.:

AF XY:

0.0000469

AC XY:

AN XY:

724690

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000558

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000398

AC:

AN:

150654

Hom.:

Cov.:

AF XY:

0.0000272

AC XY:

AN XY:

73526

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000662

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000739

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Likely benign

Submissions summary: Benign:4

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

Oct 16, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Developmental and epileptic encephalopathy, 14

Benign:1

Mar 15, 2022

Genome-Nilou Lab

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Benign:1

Apr 29, 2019

GeneDx

Significance: Likely 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: Likely 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

-0.87

CADD

Benign

3.1

DANN

Benign

0.65

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