rs749215518

Variant summary

Our verdict is Benign. The variant received -17 ACMG points: 0P and 17B. BP4_StrongBP6_Very_StrongBP7BS2

The NM_004975.4(KCNB1):​c.1207C>T​(p.Leu403Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000093 in 1,613,172 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 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 synonymous

Scores

2

Clinical Significance

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

Conservation

PhyloP100: 1.54

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 -17 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.54).
BP6
Variant 20-49374353-G-A is Benign according to our data. Variant chr20-49374353-G-A is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 475256.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BP7
Synonymous conserved (PhyloP=1.54 with no splicing effect.
BS2
High AC in GnomAdExome4 at 13 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNB1NM_004975.4 linkc.1207C>T p.Leu403Leu synonymous_variant Exon 2 of 2 ENST00000371741.6 NP_004966.1 Q14721
KCNB1XM_011528799.3 linkc.1207C>T p.Leu403Leu synonymous_variant Exon 3 of 3 XP_011527101.1 Q14721
LOC105372649XR_001754659.2 linkn.1201+42329G>A intron_variant Intron 2 of 3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNB1ENST00000371741.6 linkc.1207C>T p.Leu403Leu synonymous_variant Exon 2 of 2 1 NM_004975.4 ENSP00000360806.3 Q14721
KCNB1ENST00000635465.1 linkc.1207C>T p.Leu403Leu synonymous_variant Exon 3 of 3 1 ENSP00000489193.1 Q14721
KCNB1ENST00000635878.1 linkc.97-74970C>T intron_variant Intron 1 of 2 5 ENSP00000489908.1 A0A1B0GU02
ENSG00000290421ENST00000637341.1 linkn.206+42329G>A intron_variant Intron 2 of 7 5

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152210
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000131
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000359
AC:
9
AN:
250506
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000260
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000890
AC:
13
AN:
1460962
Hom.:
0
Cov.:
33
AF XY:
0.00000550
AC XY:
4
AN XY:
726848
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000201
AC:
9
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:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52508
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111998
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
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:
0.0000131
AC:
2
AN:
152210
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41444
American (AMR)
AF:
0.000131
AC:
2
AN:
15288
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68042
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
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
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not specified Benign:1
Sep 30, 2024
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Developmental and epileptic encephalopathy, 26 Benign:1
Nov 03, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.54
CADD
Benign
5.8
DANN
Benign
0.76
PhyloP100
1.5

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: rs749215518; hg19: chr20-47990890; API