9-135768871-G-A

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 3P and 4B. PM1PP3BS2

The NM_020822.3(KCNT1):c.1444G>A(p.Ala482Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000868 in 1,613,240 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.77

Publications

1 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, G2P, Labcorp Genetics (formerly Invitae)
malignant migrating partial seizures of infancy
Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, G2P
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 -1 ACMG points.

PM1

In a hotspot region, there are 8 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_020822.3

PP3

MetaRNN computational evidence supports a deleterious effect, 0.752

BS2

High AC in GnomAdExome4 at 12 AD gene.

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.1444G>A	p.Ala482Thr	missense	Exon 15 of 31	NP_065873.2	Q5JUK3-3
	KCNT1	NM_001272003.2		c.1309G>A	p.Ala437Thr	missense	Exon 14 of 31	NP_001258932.1	Q5JUK3-4

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
KCNT1	ENST00000371757.7	TSL:1 MANE Select	c.1444G>A	p.Ala482Thr	missense	Exon 15 of 31	ENSP00000360822.2	Q5JUK3-3
KCNT1	ENST00000460750.5	TSL:1	n.*1054G>A		non_coding_transcript_exon	Exon 15 of 32	ENSP00000418777.1	F8WC49
KCNT1	ENST00000460750.5	TSL:1	n.*1054G>A		3_prime_UTR	Exon 15 of 32	ENSP00000418777.1	F8WC49

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152164

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000654

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.00

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000400

AC:

AN:

249788

AF XY:

0.00

show subpopulations

Gnomad AFR exome

AF:

0.00

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:

0.00000821

AC:

AN:

1460958

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

726836

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33470

American (AMR)

AF:

0.00

AC:

AN:

44704

Ashkenazi Jewish (ASJ)

AF:

0.0000383

AC:

AN:

26114

East Asian (EAS)

AF:

0.00

AC:

AN:

39694

South Asian (SAS)

AF:

0.0000232

AC:

AN:

86222

European-Finnish (FIN)

AF:

0.00

AC:

AN:

52772

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5746

European-Non Finnish (NFE)

AF:

0.00000809

AC:

AN:

1111872

Other (OTH)

AF:

0.00

AC:

AN:

60364

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.425

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:

152282

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74454

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41562

American (AMR)

AF:

0.0000654

AC:

AN:

15300

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3472

East Asian (EAS)

AF:

0.00

AC:

AN:

5158

South Asian (SAS)

AF:

0.000207

AC:

AN:

4822

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10616

Middle Eastern (MID)

AF:

0.00

AC:

AN:

292

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

68032

Other (OTH)

AF:

0.00

AC:

AN:

2116

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.575

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.00

Hom.:

ExAC

AF:

0.00000824

AC:

ClinVar

ClinVar submissions

Significance:Uncertain significance

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

AlphaMissense

Pathogenic

0.89

BayesDel_addAF

Pathogenic

0.17

BayesDel_noAF

Uncertain

0.11

CADD

Pathogenic

(source)

DANN

Pathogenic

1.0

DEOGEN2

Benign

0.40

Eigen

Uncertain

0.67

Eigen_PC

Uncertain

0.60

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

1.0

M_CAP

Uncertain

0.21

MetaRNN

Pathogenic

0.75

MetaSVM

Uncertain

0.00020

MutationAssessor

Uncertain

2.6

PhyloP100

9.8

PrimateAI

Pathogenic

0.79

PROVEAN

Uncertain

-3.8

REVEL

Pathogenic

0.65

Sift

Uncertain

0.0010

Sift4G

Pathogenic

0.0

Polyphen

0.98

Vest4

0.84

MutPred

0.53

Loss of loop (P = 0.0203)

MVP

0.77

MPC

1.6

ClinPred

1.0

GERP RS

3.8

Varity_R

0.74

gMVP

0.86

Mutation Taster

=24/76

disease causing

(source)

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

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