rs1433727837

Positions:

chr1-110604539-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM2PP2PP3_Strong

The NM_004974.4(KCNA2):c.244C>T(p.Arg82Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,461,890 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R82H) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

KCNA2
NM_004974.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 5.08

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 links:

KCNA2 (HGNC:):

KCNA2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), KCNA2. . Gene score misZ 3.831 (greater than the threshold 3.09). Trascript score misZ 5.1665 (greater than threshold 3.09). GenCC has associacion of gene with undetermined early-onset epileptic encephalopathy, developmental and epileptic encephalopathy, developmental and epileptic encephalopathy, 32.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.974

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNA2	NM_004974.4 linkuse as main transcript	c.244C>T	p.Arg82Cys	missense_variant	3/3	ENST00000316361.10	NP_004965.1	P16389-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNA2	ENST00000316361.10 linkuse as main transcript	c.244C>T	p.Arg82Cys	missense_variant	3/3	2	NM_004974.4	ENSP00000314520.4		P16389-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251442

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135902

show subpopulations

Gnomad AFR exome

AF:

0.0000616

Gnomad AMR exome

AF:

0.00

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:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1461890

Hom.:

Cov.:

AF XY:

0.00000413

AC XY:

AN XY:

727246

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000187

Gnomad4 NFE exome

AF:

0.00000180

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 32

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 13, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 542665). This variant has not been reported in the literature in individuals affected with KCNA2-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.007%). This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 82 of the KCNA2 protein (p.Arg82Cys). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

1.0

BayesDel_addAF

Pathogenic

0.22

BayesDel_noAF

Pathogenic

0.26

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.95

D;.;D;D;D;D

Eigen

Pathogenic

0.84

Eigen_PC

Pathogenic

0.75

FATHMM_MKL

Uncertain

0.95

LIST_S2

Pathogenic

1.0

.;D;.;.;.;D

M_CAP

Uncertain

0.27

MetaRNN

Pathogenic

0.97

D;D;D;D;D;D

MetaSVM

Uncertain

0.48

MutationAssessor

Pathogenic

4.0

H;H;H;H;H;H

PrimateAI

Pathogenic

0.92

PROVEAN

Pathogenic

-6.9

.;D;.;D;.;D

REVEL

Pathogenic

0.79

Sift

Pathogenic

0.0

.;D;.;D;.;D

Sift4G

Pathogenic

0.0

D;D;.;D;.;D

Polyphen

1.0

D;.;D;D;D;D

Vest4

0.77

MutPred

0.90

Gain of catalytic residue at R80 (P = 0.0618);Gain of catalytic residue at R80 (P = 0.0618);Gain of catalytic residue at R80 (P = 0.0618);Gain of catalytic residue at R80 (P = 0.0618);Gain of catalytic residue at R80 (P = 0.0618);Gain of catalytic residue at R80 (P = 0.0618);

MVP

0.94

MPC

2.7

ClinPred

1.0

GERP RS

4.8

Varity_R

0.69

gMVP

0.92

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

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