NM_004975.4:c.2327A>G

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_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. 16/22 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

3
16

Clinical Significance

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

Conservation

PhyloP100: 1.45

Publications

0 publications found
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 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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -14 ACMG points.

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 rank MANE Protein UniProt
KCNB1NM_004975.4 linkc.2327A>G p.Lys776Arg missense_variant Exon 2 of 2 ENST00000371741.6 NP_004966.1 Q14721
KCNB1XM_011528799.3 linkc.2327A>G p.Lys776Arg missense_variant Exon 3 of 3 XP_011527101.1 Q14721
LOC105372649XR_001754659.2 linkn.1201+41209T>C intron_variant Intron 2 of 3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNB1ENST00000371741.6 linkc.2327A>G p.Lys776Arg missense_variant Exon 2 of 2 1 NM_004975.4 ENSP00000360806.3 Q14721

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
152084
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000318
AC:
8
AN:
251374
AF XY:
0.0000221
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:
0.0000616
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000239
AC:
35
AN:
1461888
Hom.:
0
Cov.:
32
AF XY:
0.0000220
AC XY:
16
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000261
AC:
29
AN:
1112006
Other (OTH)
AF:
0.0000993
AC:
6
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
3
6
9
12
15
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<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:
0.0000395
AC:
6
AN:
152084
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74272
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41428
American (AMR)
AF:
0.00
AC:
0
AN:
15268
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4826
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10590
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68004
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000160
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000412
AC:
5
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
Oct 03, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Benign:1
Oct 21, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.068
BayesDel_addAF
Benign
-0.26
T
BayesDel_noAF
Benign
-0.29
CADD
Benign
15
DANN
Uncertain
0.99
DEOGEN2
Benign
0.28
T;T
Eigen
Benign
-0.054
Eigen_PC
Benign
0.042
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.59
.;T
M_CAP
Benign
0.073
D
MetaRNN
Benign
0.12
T;T
MetaSVM
Uncertain
0.25
D
MutationAssessor
Benign
0.69
N;N
PhyloP100
1.5
PrimateAI
Benign
0.33
T
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
T
GERP RS
3.2
Varity_R
0.053
gMVP
0.14
Mutation Taster
=91/9
polymorphism

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

Other links and lift over

dbSNP: rs756982426; hg19: chr20-47989770; API