NM_020822.3:c.1365C>T

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_ModerateBP6_ModerateBP7

The NM_020822.3(KCNT1):c.1365C>T(p.Ile455Ile) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000387 in 1,550,458 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 (★). Synonymous variant affecting the same amino acid position (i.e. I455I) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 30)

Exomes 𝑓: 0.0000029 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 synonymous

Scores

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 0.319

Publications

0 publications found

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 Gene-Disease associations (from GenCC):

childhood-onset epilepsy syndrome
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
developmental and epileptic encephalopathy, 14
Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P
malignant migrating partial seizures of infancy
Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, Orphanet
autosomal dominant nocturnal frontal lobe epilepsy 5
Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
autosomal dominant nocturnal frontal lobe epilepsy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

KCNT1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.42).

BP6

Variant 9-135768637-C-T is Benign according to our data. Variant chr9-135768637-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 540593.Status of the report is criteria_provided_single_submitter, 1 stars.

BP7

Synonymous conserved (PhyloP=0.319 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_020822.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNT1	NM_020822.3	MANE Select	c.1365C>T	p.Ile455Ile	synonymous	Exon 14 of 31	NP_065873.2
	KCNT1	NM_001272003.2		c.1230C>T	p.Ile410Ile	synonymous	Exon 13 of 31	NP_001258932.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
KCNT1	ENST00000371757.7	TSL:1 MANE Select	c.1365C>T	p.Ile455Ile	synonymous	Exon 14 of 31	ENSP00000360822.2
KCNT1	ENST00000460750.5	TSL:1	n.*975C>T		non_coding_transcript_exon	Exon 14 of 32	ENSP00000418777.1
KCNT1	ENST00000460750.5	TSL:1	n.*975C>T		3_prime_UTR	Exon 14 of 32	ENSP00000418777.1

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152116

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000641

AC:

AN:

156004

AF XY:

0.00

show subpopulations

Gnomad AFR exome

AF:

0.000115

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000286

AC:

AN:

1398342

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

689718

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

31590

American (AMR)

AF:

0.00

AC:

AN:

35702

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

25166

East Asian (EAS)

AF:

0.000112

AC:

AN:

35738

South Asian (SAS)

AF:

0.00

AC:

AN:

79224

European-Finnish (FIN)

AF:

0.00

AC:

AN:

48392

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5682

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1078858

Other (OTH)

AF:

0.00

AC:

AN:

57990

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.488

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<30

30-35

35-40

40-45

45-50

50-55

55-60

60-65

65-70

70-75

75-80

>80

Age

GnomAD4 genome

AF:

0.0000131

AC:

AN:

152116

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74306

show subpopulations

African (AFR)

AF:

0.0000483

AC:

AN:

41412

American (AMR)

AF:

0.00

AC:

AN:

15284

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5160

South Asian (SAS)

AF:

0.00

AC:

AN:

4834

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10620

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68014

Other (OTH)

AF:

0.00

AC:

AN:

2092

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.525

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.0000113

ClinVar

ClinVar submissions as Germline

Significance:Likely benign

Revision:criteria provided, single submitter

View on ClinVar

Pathogenic

VUS

Benign

Condition

Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.42

CADD

Benign

(source)

DANN

Benign

0.90

PhyloP100

0.32

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.060

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over