3-178842933-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_181361.3(KCNMB2):c.704G>A(p.Arg235Lys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000211 in 1,594,920 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 Uncertain significance (★).

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00022 ( 0 hom. )

Consequence

KCNMB2
NM_181361.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.07

Variant links:

Genes affected

KCNMB2 (HGNC:6286): (potassium calcium-activated channel subfamily M regulatory beta subunit 2) MaxiK channels are large conductance, voltage and calcium-sensitive potassium channels which are fundamental to the control of smooth muscle tone and neuronal excitability. MaxiK channels can be formed by 2 subunits: the pore-forming alpha subunit and the modulatory beta subunit. The protein encoded by this gene is an auxiliary beta subunit which decreases the activation time of MaxiK alpha subunit currents. Alternative splicing results in multiple transcript variants of this gene. Additional variants are discussed in the literature, but their full length nature has not been described. [provided by RefSeq, Jul 2013]

KCNMB2 links:

KCNMB2-AS1 (HGNC:51409): (KCNMB2 antisense RNA 1)

KCNMB2-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.3095932).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNMB2	NM_181361.3 linkuse as main transcript	c.704G>A	p.Arg235Lys	missense_variant	5/5	ENST00000452583.6
KCNMB2-AS1	NR_126560.1 linkuse as main transcript	n.247+16556C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNMB2	ENST00000452583.6 linkuse as main transcript	c.704G>A	p.Arg235Lys	missense_variant	5/5	1	NM_181361.3	P1
KCNMB2-AS1	ENST00000437488.5 linkuse as main transcript	n.194+16556C>T		intron_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes

AF:

0.000118

AC:

AN:

152096

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:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000250

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000635

AC:

AN:

236074

Hom.:

AF XY:

0.0000859

AC XY:

AN XY:

128010

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:

0.000138

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000220

AC:

318

AN:

1442824

Hom.:

Cov.:

AF XY:

0.000225

AC XY:

161

AN XY:

716136

show subpopulations

Gnomad4 AFR exome

AF:

0.0000308

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000253

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000280

Gnomad4 OTH exome

AF:

0.000118

GnomAD4 genome

AF:

0.000118

AC:

AN:

152096

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74298

show subpopulations

Gnomad4 AFR

AF:

0.0000241

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:

0.000250

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000164

Hom.:

Bravo

AF:

0.000113

ExAC

AF:

0.0000494

AC:

EpiCase

AF:

0.000218

EpiControl

AF:

0.000178

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 10, 2021

The c.704G>A (p.R235K) alteration is located in exon 5 (coding exon 4) of the KCNMB2 gene. This alteration results from a G to A substitution at nucleotide position 704, causing the arginine (R) at amino acid position 235 to be replaced by a lysine (K). 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

Benign

0.32

BayesDel_addAF

Benign

-0.16

BayesDel_noAF

Benign

-0.24

Cadd

Uncertain

Dann

Uncertain

1.0

DEOGEN2

Benign

0.046

T;T;T;T;.;.

Eigen

Uncertain

0.68

Eigen_PC

Pathogenic

0.74

FATHMM_MKL

Pathogenic

1.0

M_CAP

Benign

0.022

MetaRNN

Benign

0.31

T;T;T;T;T;T

MetaSVM

Benign

-1.1

MutationAssessor

Benign

0.94

L;L;L;L;.;.

MutationTaster

Benign

1.0

D;D;D;D

PrimateAI

Uncertain

0.74

PROVEAN

Benign

-0.76

N;N;N;N;.;.

REVEL

Benign

0.21

Sift

Pathogenic

0.0

D;D;D;D;.;.

Sift4G

Pathogenic

0.0

D;D;D;D;D;D

Polyphen

0.98

D;D;D;D;.;.

Vest4

0.62

MVP

0.24

MPC

0.98

ClinPred

0.29

GERP RS

5.8

Varity_R

0.58

gMVP

0.72

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