rs774976039

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 1P and 8B. PP2BP4_ModerateBP6_ModerateBS2

The NM_004975.4(KCNB1):​c.2152G>A​(p.Val718Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000623 in 1,604,948 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 Benign (★).

Frequency

Genomes: 𝑓 0.000014 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000055 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 missense

Scores

4
15

Clinical Significance

Benign criteria provided, single submitter B:1

Conservation

PhyloP100: 0.0410
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -7 ACMG points.

PP2
Missense variant in the KCNB1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 76 curated pathogenic missense variants (we use a threshold of 10). The gene has 110 curated benign missense variants. Gene score misZ: 4.269 (above the threshold of 3.09). Trascript score misZ: 5.3923 (above the threshold of 3.09). GenCC associations: The gene is linked to undetermined early-onset epileptic encephalopathy, complex neurodevelopmental disorder, developmental and epileptic encephalopathy, 26.
BP4
Computational evidence support a benign effect (MetaRNN=0.08774066).
BP6
Variant 20-49373408-C-T is Benign according to our data. Variant chr20-49373408-C-T is described in ClinVar as [Benign]. Clinvar id is 542056.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr20-49373408-C-T is described in Lovd as [Likely_benign].
BS2
High AC in GnomAdExome4 at 8 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNB1NM_004975.4 linkc.2152G>A p.Val718Met missense_variant Exon 2 of 2 ENST00000371741.6 NP_004966.1 Q14721
KCNB1XM_011528799.3 linkc.2152G>A p.Val718Met missense_variant Exon 3 of 3 XP_011527101.1 Q14721
LOC105372649XR_001754659.2 linkn.1201+41384C>T intron_variant Intron 2 of 3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNB1ENST00000371741.6 linkc.2152G>A p.Val718Met missense_variant Exon 2 of 2 1 NM_004975.4 ENSP00000360806.3 Q14721
KCNB1ENST00000635465.1 linkc.2152G>A p.Val718Met missense_variant Exon 3 of 3 1 ENSP00000489193.1 Q14721
KCNB1ENST00000635878.1 linkc.97-74025G>A intron_variant Intron 1 of 2 5 ENSP00000489908.1 A0A1B0GU02
ENSG00000290421ENST00000637341.1 linkn.206+41384C>T intron_variant Intron 2 of 7 5

Frequencies

GnomAD3 genomes
AF:
0.0000139
AC:
2
AN:
144284
Hom.:
0
Cov.:
32
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:
0.0000309
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251040
Hom.:
0
AF XY:
0.00000737
AC XY:
1
AN XY:
135658
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:
0.00000882
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000548
AC:
8
AN:
1460664
Hom.:
0
Cov.:
32
AF XY:
0.00000826
AC XY:
6
AN XY:
726600
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:
0.00000720
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000139
AC:
2
AN:
144284
Hom.:
0
Cov.:
32
AF XY:
0.0000141
AC XY:
1
AN XY:
70700
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:
0.0000309
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000756
Hom.:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Benign
Submissions summary: Benign:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 26 Benign:1
Sep 05, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.092
BayesDel_addAF
Benign
-0.039
T
BayesDel_noAF
Benign
-0.29
CADD
Benign
14
DANN
Uncertain
0.99
DEOGEN2
Benign
0.24
T;T
Eigen
Benign
-0.47
Eigen_PC
Benign
-0.47
FATHMM_MKL
Benign
0.21
N
LIST_S2
Benign
0.74
.;T
M_CAP
Benign
0.034
D
MetaRNN
Benign
0.088
T;T
MetaSVM
Uncertain
0.099
D
MutationAssessor
Benign
1.0
L;L
PrimateAI
Benign
0.33
T
PROVEAN
Benign
-0.31
N;.
REVEL
Benign
0.21
Sift
Uncertain
0.024
D;.
Sift4G
Uncertain
0.033
D;D
Polyphen
0.35
B;B
Vest4
0.073
MutPred
0.24
Gain of disorder (P = 0.0514);Gain of disorder (P = 0.0514);
MVP
0.38
MPC
0.19
ClinPred
0.045
T
GERP RS
0.55
Varity_R
0.059
gMVP
0.22

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.

Other links and lift over

dbSNP: rs774976039; hg19: chr20-47989945; API