12-75048298-A-C

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 1P and 5B. PP2BS1_SupportingBS2

The NM_139137.4(KCNC2):c.1635T>G(p.Ser545Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000931 in 1,612,036 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Uncertain significance in ClinVar.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000082 ( 0 hom. )

Consequence

KCNC2
NM_139137.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.93

Variant links:

Genes affected

KCNC2 (HGNC:6234): (potassium voltage-gated channel subfamily C member 2) The Shaker gene family of Drosophila encodes components of voltage-gated potassium channels and is comprised of four subfamilies. Based on sequence similarity, this gene is similar to one of these subfamilies, namely the Shaw subfamily. The protein encoded by this gene belongs to the delayed rectifier class of channel proteins and is an integral membrane protein that mediates the voltage-dependent potassium ion permeability of excitable membranes. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2012]

KCNC2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -4 ACMG points.

PP2

Missense variant in the KCNC2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 11 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 2.9757 (below the threshold of 3.09). Trascript score misZ: 3.1921 (above the threshold of 3.09). GenCC associations: The gene is linked to developmental and epileptic encephalopathy 103, developmental and epileptic encephalopathy.

BS1

Variant frequency is greater than expected in population amr. gnomad4_exome allele frequency = 0.00000822 (12/1460080) while in subpopulation AMR AF= 0.000157 (7/44528). AF 95% confidence interval is 0.0000731. There are 0 homozygotes in gnomad4_exome. There are 6 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

BS2

High AC in GnomAdExome4 at 12 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNC2	NM_139137.4 link	c.1635T>G	p.Ser545Arg	missense_variant	Exon 4 of 5	ENST00000549446.6	NP_631875.1	Q96PR1-1A0A024RBA5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNC2	ENST00000549446.6 link	c.1635T>G	p.Ser545Arg	missense_variant	Exon 4 of 5	1	NM_139137.4	ENSP00000449253.2		Q96PR1-1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

151956

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000242

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000131

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

GnomAD3 exomes

AF:

0.0000280

AC:

AN:

249640

Hom.:

AF XY:

0.0000296

AC XY:

AN XY:

134950

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.000146

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:

0.00000822

AC:

AN:

1460080

Hom.:

Cov.:

AF XY:

0.00000826

AC XY:

AN XY:

726352

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.000157

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000450

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

151956

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74194

show subpopulations

Gnomad4 AFR

AF:

0.0000242

Gnomad4 AMR

AF:

0.000131

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000283

Hom.:

Bravo

AF:

0.0000340

ExAC

AF:

0.0000247

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Apr 27, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.1635T>G (p.S545R) alteration is located in exon 4 (coding exon 3) of the KCNC2 gene. This alteration results from a T to G substitution at nucleotide position 1635, causing the serine (S) at amino acid position 545 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.49

BayesDel_addAF

Pathogenic

0.27

BayesDel_noAF

Pathogenic

0.41

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.27

.;.;T;.;.

Eigen

Uncertain

0.37

Eigen_PC

Uncertain

0.42

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.90

D;.;D;D;D

M_CAP

Benign

0.083

MetaRNN

Uncertain

0.47

T;T;T;T;T

MetaSVM

Uncertain

0.41

MutationAssessor

Benign

2.0

M;M;M;M;M

PrimateAI

Uncertain

0.58

PROVEAN

Benign

-1.4

N;N;N;N;N

REVEL

Uncertain

0.53

Sift

Benign

0.20

T;T;T;T;T

Sift4G

Benign

0.10

T;T;T;T;T

Polyphen

0.87

P;D;P;D;.

Vest4

0.64

MutPred

0.18

Loss of phosphorylation at S545 (P = 0.013);Loss of phosphorylation at S545 (P = 0.013);Loss of phosphorylation at S545 (P = 0.013);Loss of phosphorylation at S545 (P = 0.013);Loss of phosphorylation at S545 (P = 0.013);

MVP

0.83

MPC

1.8

ClinPred

0.37

GERP RS

5.5

Varity_R

0.23

gMVP

0.51

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