chr20-49373233-T-C

Position:

chr20-49373233-T-C

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 1P and 14B. PP2BP4_ModerateBP6_Very_StrongBS2

The NM_004975.4(KCNB1):c.2327A>G(p.Lys776Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000254 in 1,613,972 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000024 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 missense

Scores

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:2

Conservation

PhyloP100: 1.45

Variant links:

Genes affected

KCNB1 (HGNC:6231): (potassium voltage-gated channel subfamily B member 1) Voltage-gated potassium (Kv) 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, shab-related subfamily. This member is a delayed rectifier potassium channel and its activity is modulated by some other family members. [provided by RefSeq, Jul 2008]

KCNB1 links:

(HGNC:):

links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -13 ACMG points.

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), KCNB1. . Gene score misZ 4.269 (greater than the threshold 3.09). Trascript score misZ 5.3923 (greater than threshold 3.09). GenCC has associacion of gene with undetermined early-onset epileptic encephalopathy, complex neurodevelopmental disorder, developmental and epileptic encephalopathy, 26.

BP4

Computational evidence support a benign effect (MetaRNN=0.12239483).

BP6

Variant 20-49373233-T-C is Benign according to our data. Variant chr20-49373233-T-C is described in ClinVar as [Likely_benign]. Clinvar id is 578493.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BS2

High AC in GnomAd4 at 6 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
KCNB1	NM_004975.4 linkuse as main transcript	c.2327A>G	p.Lys776Arg	missense_variant	2/2	ENST00000371741.6
LOC105372649	XR_001754659.2 linkuse as main transcript	n.1201+41209T>C		intron_variant, non_coding_transcript_variant
KCNB1	XM_011528799.3 linkuse as main transcript	c.2327A>G	p.Lys776Arg	missense_variant	3/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
KCNB1	ENST00000371741.6 linkuse as main transcript	c.2327A>G	p.Lys776Arg	missense_variant	2/2	1	NM_004975.4	P1
KCNB1	ENST00000635465.1 linkuse as main transcript	c.2327A>G	p.Lys776Arg	missense_variant	3/3	1		P1
	ENST00000637341.1 linkuse as main transcript	n.206+41209T>C		intron_variant, non_coding_transcript_variant		5
KCNB1	ENST00000635878.1 linkuse as main transcript	c.97-73850A>G		intron_variant		5

Frequencies

GnomAD3 genomes

AF:

0.0000395

AC:

AN:

152084

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:

0.0000882

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000318

AC:

AN:

251374

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135850

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000616

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000239

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.0000220

AC XY:

AN XY:

727242

show subpopulations

Gnomad4 AFR exome

AF:

0.00

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:

0.00

Gnomad4 NFE exome

AF:

0.0000261

Gnomad4 OTH exome

AF:

0.0000993

GnomAD4 genome

AF:

0.0000395

AC:

AN:

152084

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74272

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000882

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000160

Hom.:

Bravo

AF:

0.00000756

ExAC

AF:

0.0000412

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 26

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Oct 03, 2023

- -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Oct 21, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.068

BayesDel_addAF

Benign

-0.26

BayesDel_noAF

Benign

-0.29

CADD

Benign

DANN

Uncertain

0.99

DEOGEN2

Benign

0.28

T;T

Eigen

Benign

-0.054

Eigen_PC

Benign

0.042

FATHMM_MKL

Uncertain

0.93

LIST_S2

Benign

0.59

.;T

M_CAP

Benign

0.073

MetaRNN

Benign

0.12

T;T

MetaSVM

Uncertain

0.25

MutationAssessor

Benign

0.69

N;N

MutationTaster

Benign

0.81

PrimateAI

Benign

0.33

PROVEAN

Benign

-0.48

N;.

REVEL

Benign

0.26

Sift

Benign

0.27

T;.

Sift4G

Benign

0.31

T;T

Polyphen

0.38

B;B

Vest4

0.051

MutPred

0.26

Loss of ubiquitination at K776 (P = 1e-04);Loss of ubiquitination at K776 (P = 1e-04);

MVP

0.72

MPC

0.15

ClinPred

0.042

GERP RS

3.2

Varity_R

0.053

gMVP

0.14

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