NM_004975.4:c.1997C>T

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4BP6_Very_StrongBS2

The NM_004975.4(KCNB1):​c.1997C>T​(p.Pro666Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00011 in 1,614,000 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 0.000092 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 missense

Scores

1
10
8

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:5

Conservation

PhyloP100: 6.48

Publications

4 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 -13 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.32633734).
BP6
Variant 20-49373563-G-A is Benign according to our data. Variant chr20-49373563-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 385555.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAd4 at 14 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNB1NM_004975.4 linkc.1997C>T p.Pro666Leu missense_variant Exon 2 of 2 ENST00000371741.6 NP_004966.1 Q14721
KCNB1XM_011528799.3 linkc.1997C>T p.Pro666Leu missense_variant Exon 3 of 3 XP_011527101.1 Q14721
LOC105372649XR_001754659.2 linkn.1201+41539G>A intron_variant Intron 2 of 3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNB1ENST00000371741.6 linkc.1997C>T p.Pro666Leu missense_variant Exon 2 of 2 1 NM_004975.4 ENSP00000360806.3 Q14721
KCNB1ENST00000635465.1 linkc.1997C>T p.Pro666Leu missense_variant Exon 3 of 3 1 ENSP00000489193.1 Q14721
KCNB1ENST00000635878.1 linkc.97-74180C>T intron_variant Intron 1 of 2 5 ENSP00000489908.1 A0A1B0GU02
ENSG00000290421ENST00000637341.1 linkn.206+41539G>A intron_variant Intron 2 of 7 5

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152150
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000655
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:
0.000191
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000139
AC:
35
AN:
251264
AF XY:
0.000162
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.0000993
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000264
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.000112
AC:
164
AN:
1461850
Hom.:
0
Cov.:
32
AF XY:
0.000128
AC XY:
93
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000134
AC:
6
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:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53386
Middle Eastern (MID)
AF:
0.00225
AC:
13
AN:
5768
European-Non Finnish (NFE)
AF:
0.000119
AC:
132
AN:
1112002
Other (OTH)
AF:
0.000199
AC:
12
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.480
Heterozygous variant carriers
0
10
20
30
40
50
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000920
AC:
14
AN:
152150
Hom.:
0
Cov.:
32
AF XY:
0.0000942
AC XY:
7
AN XY:
74322
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41424
American (AMR)
AF:
0.0000655
AC:
1
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3468
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.000191
AC:
13
AN:
68028
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.532
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.000184
Hom.:
0
Bravo
AF:
0.0000907
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.000165
AC:
20
EpiCase
AF:
0.000654
EpiControl
AF:
0.000889

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:5
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Benign:3
-
Breakthrough Genomics, Breakthrough Genomics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:not provided

- -

Aug 31, 2020
GeneDx
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 01, 2021
CeGaT Center for Human Genetics Tuebingen
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Developmental and epileptic encephalopathy, 26 Benign:1
Dec 28, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Benign:1
May 24, 2023
Ambry Genetics
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.21
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.13
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.55
D;D
Eigen
Uncertain
0.63
Eigen_PC
Uncertain
0.65
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.84
.;T
M_CAP
Benign
0.045
D
MetaRNN
Benign
0.33
T;T
MetaSVM
Benign
-0.68
T
MutationAssessor
Uncertain
2.5
M;M
PhyloP100
6.5
PrimateAI
Uncertain
0.51
T
PROVEAN
Uncertain
-3.5
D;.
REVEL
Uncertain
0.39
Sift
Uncertain
0.0010
D;.
Sift4G
Uncertain
0.0050
D;D
Polyphen
0.87
P;P
Vest4
0.35
MVP
0.57
MPC
0.35
ClinPred
0.22
T
GERP RS
5.7
Varity_R
0.28
gMVP
0.58
Mutation Taster
=68/32
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: rs201212125; hg19: chr20-47990100; COSMIC: COSV65565978; COSMIC: COSV65565978; API