20-49373044-G-A

Variant summary

Our verdict is Benign. The variant received -11 ACMG points: 1P and 12B. PP3BP6_Very_StrongBS2

The NM_004975.4(KCNB1):​c.2516C>T​(p.Pro839Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000143 in 1,614,024 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P839T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 missense

Scores

7
8
4

Clinical Significance

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

Conservation

PhyloP100: 3.37

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 -11 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.763
BP6
Variant 20-49373044-G-A is Benign according to our data. Variant chr20-49373044-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 475262.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAdExome4 at 20 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNB1NM_004975.4 linkc.2516C>T p.Pro839Leu missense_variant Exon 2 of 2 ENST00000371741.6 NP_004966.1 Q14721
KCNB1XM_011528799.3 linkc.2516C>T p.Pro839Leu missense_variant Exon 3 of 3 XP_011527101.1 Q14721
LOC105372649XR_001754659.2 linkn.1201+41020G>A intron_variant Intron 2 of 3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNB1ENST00000371741.6 linkc.2516C>T p.Pro839Leu missense_variant Exon 2 of 2 1 NM_004975.4 ENSP00000360806.3 Q14721

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152156
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251354
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:
0.0000440
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000137
AC:
20
AN:
1461868
Hom.:
0
Cov.:
32
AF XY:
0.0000179
AC XY:
13
AN XY:
727236
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:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
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:
5760
European-Non Finnish (NFE)
AF:
0.0000180
AC:
20
AN:
1112000
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.0000197
AC:
3
AN:
152156
Hom.:
0
Cov.:
32
AF XY:
0.0000269
AC XY:
2
AN XY:
74322
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41446
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68018
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.592
Heterozygous variant carriers
0
1
1
2
2
3
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:
0.00
Hom.:
0
Bravo
AF:
0.0000264
ExAC
AF:
0.00000824
AC:
1
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 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Benign:1
Jan 11, 2018
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.16
BayesDel_addAF
Pathogenic
0.21
D
BayesDel_noAF
Pathogenic
0.18
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Uncertain
0.61
D;D
Eigen
Uncertain
0.65
Eigen_PC
Uncertain
0.64
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Uncertain
0.87
.;D
M_CAP
Pathogenic
0.44
D
MetaRNN
Pathogenic
0.76
D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
0.90
L;L
PhyloP100
3.4
PrimateAI
Uncertain
0.53
T
PROVEAN
Uncertain
-2.4
N;.
REVEL
Pathogenic
0.76
Sift
Benign
0.077
T;.
Sift4G
Uncertain
0.0040
D;D
Polyphen
0.98
D;D
Vest4
0.49
MutPred
0.57
Loss of disorder (P = 0.0149);Loss of disorder (P = 0.0149);
MVP
0.74
MPC
0.49
ClinPred
0.67
D
GERP RS
5.6
Varity_R
0.087
gMVP
0.73
Mutation Taster
=51/49
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: rs761070687; hg19: chr20-47989581; API