20-49374255-A-G

Position:

chr20-49374255-A-G

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_StrongBP6_Very_StrongBP7BS1BS2

The NM_004975.4(KCNB1):c.1305T>C(p.Ala435=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000521 in 1,613,708 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 Likely benign (★★).

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000048 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 synonymous

Scores

Clinical Significance

Likely benign criteria provided, multiple submitters, no conflicts B:3

Conservation

PhyloP100: 0.135

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 -21 ACMG points.

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.6).

BP6

Variant 20-49374255-A-G is Benign according to our data. Variant chr20-49374255-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 384311.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

BP7

Synonymous conserved (PhyloP=0.135 with no splicing effect.

BS1

Variant frequency is greater than expected in population afr. gnomad4_exome allele frequency = 0.0000479 (70/1461470) while in subpopulation AFR AF= 0.000836 (28/33478). AF 95% confidence interval is 0.000594. There are 0 homozygotes in gnomad4_exome. There are 34 alleles in male gnomad4_exome subpopulation. Median coverage is 33. This position pass quality control queck.

BS2

High AC in GnomAd4 at 14 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
KCNB1	NM_004975.4 linkuse as main transcript	c.1305T>C	p.Ala435=	synonymous_variant	2/2	ENST00000371741.6
LOC105372649	XR_001754659.2 linkuse as main transcript	n.1201+42231A>G		intron_variant, non_coding_transcript_variant
KCNB1	XM_011528799.3 linkuse as main transcript	c.1305T>C	p.Ala435=	synonymous_variant	3/3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
KCNB1	ENST00000371741.6 linkuse as main transcript	c.1305T>C	p.Ala435=	synonymous_variant	2/2	1	NM_004975.4	P1
KCNB1	ENST00000635465.1 linkuse as main transcript	c.1305T>C	p.Ala435=	synonymous_variant	3/3	1		P1
	ENST00000637341.1 linkuse as main transcript	n.206+42231A>G		intron_variant, non_coding_transcript_variant		5
KCNB1	ENST00000635878.1 linkuse as main transcript	c.97-74872T>C		intron_variant		5

Frequencies

GnomAD3 genomes

AF:

0.0000920

AC:

AN:

152120

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000196

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:

0.000103

Gnomad OTH

AF:

0.000956

GnomAD3 exomes

AF:

0.0000398

AC:

AN:

251142

Hom.:

AF XY:

0.0000147

AC XY:

AN XY:

135788

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000327

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000616

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.0000479

AC:

AN:

1461470

Hom.:

Cov.:

AF XY:

0.0000468

AC XY:

AN XY:

727098

show subpopulations

Gnomad4 AFR exome

AF:

0.000836

Gnomad4 AMR exome

AF:

0.0000224

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:

0.0000234

Gnomad4 OTH exome

AF:

0.000182

GnomAD4 genome

AF:

0.0000920

AC:

AN:

152238

Hom.:

Cov.:

AF XY:

0.0000672

AC XY:

AN XY:

74440

show subpopulations

Gnomad4 AFR

AF:

0.0000482

Gnomad4 AMR

AF:

0.000196

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000103

Gnomad4 OTH

AF:

0.000946

Alfa

AF:

0.0000658

Hom.:

Bravo

AF:

0.0000793

Asia WGS

AF:

0.000289

AC:

AN:

3478

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Likely benign

Submissions summary: Benign:3

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

Labcorp Genetics (formerly Invitae), Labcorp

Jan 07, 2024

- -

not specified

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

GeneDx

Oct 24, 2017

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

not provided

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Jan 01, 2023

KCNB1: BP4, BP7 -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.60

CADD

Benign

7.3

DANN

Benign

0.61

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