20-49373236-G-C

Variant names:

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBP6BS2

The NM_004975.4(KCNB1):c.2324C>G(p.Pro775Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000366 in 1,614,124 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P775A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000037 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:4

Conservation

PhyloP100: 9.45

Publications

1 publications found

Variant links:

COSMIC-nc: COSV107478237

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 Gene-Disease associations (from GenCC):

complex neurodevelopmental disorder
Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
developmental and epileptic encephalopathy, 26
Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
undetermined early-onset epileptic encephalopathy
Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

KCNB1 links:

ENSG00000290421 (HGNC:):

ENSG00000290421 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -7 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.12827235).

BP6

Variant 20-49373236-G-C is Benign according to our data. Variant chr20-49373236-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 425270.

BS2

High AC in GnomAd4 at 5 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004975.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNB1	NM_004975.4	MANE Select	c.2324C>G	p.Pro775Arg	missense	Exon 2 of 2	NP_004966.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
KCNB1	ENST00000371741.6	TSL:1 MANE Select	c.2324C>G	p.Pro775Arg	missense	Exon 2 of 2	ENSP00000360806.3
KCNB1	ENST00000635465.1	TSL:1	c.2324C>G	p.Pro775Arg	missense	Exon 3 of 3	ENSP00000489193.1
KCNB1	ENST00000635878.1	TSL:5	c.97-73853C>G		intron	N/A	ENSP00000489908.1

Frequencies

GnomAD3 genomes

AF:

0.0000329

AC:

AN:

152118

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000294

Gnomad OTH

AF:

0.000479

GnomAD2 exomes

AF:

0.0000358

AC:

AN:

251358

AF XY:

0.0000589

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:

0.0000176

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000369

AC:

AN:

1461888

Hom.:

Cov.:

AF XY:

0.0000481

AC XY:

AN XY:

727242

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:

0.000220

AC:

AN:

86258

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53420

Middle Eastern (MID)

AF:

0.000693

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.0000270

AC:

AN:

1112006

Other (OTH)

AF:

0.0000166

AC:

AN:

60396

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.489

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:

0.0000328

AC:

AN:

152236

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74426

show subpopulations

African (AFR)

AF:

0.0000241

AC:

AN:

41544

American (AMR)

AF:

0.00

AC:

AN:

15296

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3470

East Asian (EAS)

AF:

0.00

AC:

AN:

5182

South Asian (SAS)

AF:

0.000208

AC:

AN:

4818

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10604

Middle Eastern (MID)

AF:

0.00

AC:

AN:

294

European-Non Finnish (NFE)

AF:

0.0000294

AC:

AN:

68008

Other (OTH)

AF:

0.000474

AC:

AN:

2108

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.535

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Alfa

AF:

0.0000364

Hom.:

Bravo

AF:

0.0000416

ExAC

AF:

0.0000412

AC:

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

ClinVar submissions as Germline

Significance:Conflicting classifications of pathogenicity

Revision:criteria provided, conflicting classifications

View on ClinVar

Pathogenic

VUS

Benign

Condition

not provided (2)

Developmental and epileptic encephalopathy, 26 (1)

Inborn genetic diseases (1)

KCNB1-related disorder (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.081

BayesDel_addAF

Benign

-0.022

BayesDel_noAF

Uncertain

0.020

CADD

Benign

(source)

DANN

Benign

0.97

DEOGEN2

Benign

0.26

Eigen

Uncertain

0.32

Eigen_PC

Uncertain

0.43

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Benign

0.77

M_CAP

Benign

0.063

MetaRNN

Benign

0.13

MetaSVM

Uncertain

0.076

MutationAssessor

Benign

0.69

PhyloP100

9.4

PrimateAI

Benign

0.46

PROVEAN

Benign

-0.43

REVEL

Uncertain

0.42

Sift

Benign

0.15

Sift4G

Benign

0.55

Polyphen

0.54

Vest4

0.37

MutPred

0.14

Loss of glycosylation at P775 (P = 0.0076)

MVP

0.58

MPC

0.21

ClinPred

0.18

GERP RS

4.6

Varity_R

0.10

gMVP

0.38

Mutation Taster

=82/18

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

ClinVar

ClinVar submissions as Germline

Computational scores

Splicing

Publications

Other links and lift over