9-135702284-C-T

Variant names:

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_020822.3(KCNT1):c.26C>T(p.Thr9Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000106 in 1,609,068 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T9N) has been classified as Uncertain significance.

Frequency

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

Exomes 𝑓: 0.000010 ( 0 hom. )

Consequence

KCNT1
NM_020822.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -0.619

Publications

2 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 links:

SOHLH1 (HGNC:27845): (spermatogenesis and oogenesis specific basic helix-loop-helix 1) This gene encodes one of testis-specific transcription factors which are essential for spermatogenesis, oogenesis and folliculogenesis. This gene is located on chromosome 9. Mutations in this gene are associated with nonobstructive azoospermia. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2013]

SOHLH1 Gene-Disease associations (from GenCC):

ovarian dysgenesis 5
Inheritance: AR, AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
hypogonadism
Inheritance: AR Classification: LIMITED Submitted by: Ambry Genetics

SOHLH1 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.107390046).

BS2

High AC in GnomAdExome4 at 15 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNT1	NM_020822.3 link	c.26C>T	p.Thr9Ile	missense_variant	Exon 1 of 31	ENST00000371757.7	NP_065873.2	Q5JUK3-3
KCNT1	NM_001272003.2 link	c.26C>T	p.Thr9Ile	missense_variant	Exon 1 of 31		NP_001258932.1	Q5JUK3-4
SOHLH1	XM_011518698.4 link	c.-2180G>A		upstream_gene_variant			XP_011517000.1
SOHLH1	XM_006717109.5 link	c.-2309G>A		upstream_gene_variant			XP_006717172.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNT1	ENST00000371757.7 link	c.26C>T	p.Thr9Ile	missense_variant	Exon 1 of 31	1	NM_020822.3	ENSP00000360822.2		Q5JUK3-3

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151922

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000242

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.00000424

AC:

AN:

235738

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:

0.00000965

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000103

AC:

AN:

1457146

Hom.:

Cov.:

AF XY:

0.00000828

AC XY:

AN XY:

724878

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33182

American (AMR)

AF:

0.00

AC:

AN:

44548

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

25972

East Asian (EAS)

AF:

0.0000254

AC:

AN:

39442

South Asian (SAS)

AF:

0.00

AC:

AN:

86116

European-Finnish (FIN)

AF:

0.00

AC:

AN:

51850

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5716

European-Non Finnish (NFE)

AF:

0.0000126

AC:

AN:

1110156

Other (OTH)

AF:

0.00

AC:

AN:

60164

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.482

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151922

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74204

show subpopulations

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.0000242

AC:

AN:

41358

American (AMR)

AF:

0.00

AC:

AN:

15270

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5150

South Asian (SAS)

AF:

0.00

AC:

AN:

4828

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10608

Middle Eastern (MID)

AF:

0.00

AC:

AN:

314

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

67932

Other (OTH)

AF:

0.00

AC:

AN:

2080

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.029673), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.400

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.00000839

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

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

Uncertain:1

Nov 18, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces threonine, which is neutral and polar, with isoleucine, which is neutral and non-polar, at codon 9 of the KCNT1 protein (p.Thr9Ile). This variant is present in population databases (rs771423997, gnomAD 0.001%). This variant has not been reported in the literature in individuals affected with KCNT1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1408730). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt KCNT1 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Benign

-0.39

BayesDel_noAF

Benign

-0.80

CADD

Benign

(source)

DANN

Benign

0.95

Eigen

Benign

-1.2

Eigen_PC

Benign

-1.2

FATHMM_MKL

Benign

0.030

LIST_S2

Benign

0.41

T;T;T

M_CAP

Pathogenic

0.50

MetaRNN

Benign

0.11

T;T;T

MetaSVM

Benign

-1.0

PhyloP100

-0.62

PrimateAI

Uncertain

0.63

PROVEAN

Benign

-0.65

N;.;N

REVEL

Benign

0.033

Sift

Benign

0.17

T;.;D

Sift4G

Uncertain

0.017

D;T;D

Vest4

0.20

MutPred

0.27

Loss of phosphorylation at T9 (P = 0.0058);Loss of phosphorylation at T9 (P = 0.0058);Loss of phosphorylation at T9 (P = 0.0058);

MVP

0.048

MPC

0.68

ClinPred

0.028

GERP RS

1.3

PromoterAI

-0.022

Neutral

(source)

gMVP

0.19

Mutation Taster

=96/4

polymorphism

(source)

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

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

9-135702284-C-T

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over