rs1197586006

Variant names:

Variant summary

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

The NM_004974.4(KCNA2):c.1154T>C(p.Ile385Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,613,948 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 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000012 ( 0 hom. )

Consequence

KCNA2
NM_004974.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 9.32

Publications

0 publications found

Variant links:

Genes affected

KCNA2 (HGNC:6220): (potassium voltage-gated channel subfamily A member 2) 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. Four sequence-related potassium channel genes - shaker, shaw, shab, and shal - have been identified in Drosophila, and each has been shown to have human homolog(s). This gene encodes a member of the potassium channel, voltage-gated, shaker-related subfamily. This member contains six membrane-spanning domains with a shaker-type repeat in the fourth segment. It belongs to the delayed rectifier class, members of which allow nerve cells to efficiently repolarize following an action potential. The coding region of this gene is intronless, and the gene is clustered with genes KCNA3 and KCNA10 on chromosome 1. [provided by RefSeq, Jul 2008]

KCNA2 Gene-Disease associations (from GenCC):

developmental and epileptic encephalopathy, 32
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
genetic developmental and epileptic encephalopathy
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
undetermined early-onset epileptic encephalopathy
Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet

KCNA2 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 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 uncertain in NM_004974.4

PP3

MetaRNN computational evidence supports a deleterious effect, 0.758

BS2

High AC in GnomAdExome4 at 17 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNA2	NM_004974.4 link	c.1154T>C	p.Ile385Thr	missense_variant	Exon 3 of 3	ENST00000316361.10	NP_004965.1	P16389-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNA2	ENST00000316361.10 link	c.1154T>C	p.Ile385Thr	missense_variant	Exon 3 of 3	2	NM_004974.4	ENSP00000314520.4		P16389-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152108

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

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:

0.00000796

AC:

AN:

251310

AF XY:

0.0000147

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:

0.0000463

Gnomad NFE exome

AF:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000116

AC:

AN:

1461840

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

727230

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.0000187

AC:

AN:

53370

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.0000135

AC:

AN:

1112010

Other (OTH)

AF:

0.0000166

AC:

AN:

60394

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.481

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:

0.00000657

AC:

AN:

152108

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74314

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

41412

American (AMR)

AF:

0.00

AC:

AN:

15268

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5198

South Asian (SAS)

AF:

0.00

AC:

AN:

4808

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10608

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000147

AC:

AN:

68024

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

Age Distribution

Genome 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

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 32

Uncertain:1

Oct 31, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 385 of the KCNA2 protein (p.Ile385Thr). This variant is present in population databases (no rsID available, gnomAD 0.004%). This variant has not been reported in the literature in individuals affected with KCNA2-related conditions. ClinVar contains an entry for this variant (Variation ID: 542662). 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 KCNA2 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. -

Inborn genetic diseases

Uncertain:1

Aug 04, 2019

Ambry Genetics

Significance:Uncertain significance

Review Status:criteria provided, single submitter

Collection Method:clinical testing

The p.I385T variant (also known as c.1154T>C), located in coding exon 1 of the KCNA2 gene, results from a T to C substitution at nucleotide position 1154. The isoleucine at codon 385 is replaced by threonine, an amino acid with similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.38

BayesDel_addAF

Pathogenic

0.46

BayesDel_noAF

Pathogenic

0.43

CADD

Pathogenic

(source)

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.86

D;.;.;D;D;D;D;.

Eigen

Uncertain

0.42

Eigen_PC

Uncertain

0.55

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.92

.;D;D;.;.;.;D;D

M_CAP

Uncertain

0.17

MetaRNN

Pathogenic

0.76

D;D;D;D;D;D;D;D

MetaSVM

Uncertain

0.78

MutationAssessor

Benign

0.15

N;.;.;N;N;N;N;.

PhyloP100

9.3

PrimateAI

Pathogenic

0.88

PROVEAN

Uncertain

-3.1

.;.;.;.;D;.;D;.

REVEL

Pathogenic

0.80

Sift

Benign

0.030

.;.;.;.;D;.;D;.

Sift4G

Benign

0.24

T;.;.;.;T;.;T;.

Polyphen

0.68

P;.;.;P;P;P;P;.

Vest4

0.78

MutPred

0.59

Gain of disorder (P = 0.03);.;.;Gain of disorder (P = 0.03);Gain of disorder (P = 0.03);Gain of disorder (P = 0.03);Gain of disorder (P = 0.03);.;

MVP

0.98

MPC

2.4

ClinPred

0.68

GERP RS

5.8

Varity_R

0.48

gMVP

0.86

Mutation Taster

=43/57

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

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

Age Distribution

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over