20-49373713-G-C

Variant summary

Our verdict is Benign. The variant received -20 ACMG points: 0P and 20B. BP4_StrongBP6_Very_StrongBS1BS2

The NM_004975.4(KCNB1):​c.1847C>G​(p.Thr616Ser) variant causes a missense change. The variant allele was found at a frequency of 0.0183 in 1,614,164 control chromosomes in the GnomAD database, including 328 homozygotes. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Benign (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T616I) has been classified as Benign.

Frequency

Genomes: 𝑓 0.015 ( 19 hom., cov: 32)
Exomes 𝑓: 0.019 ( 309 hom. )

Consequence

KCNB1
NM_004975.4 missense

Scores

17

Clinical Significance

Benign criteria provided, multiple submitters, no conflicts B:4

Conservation

PhyloP100: 4.96

Publications

11 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: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
  • 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 -20 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.0023046434).
BP6
Variant 20-49373713-G-C is Benign according to our data. Variant chr20-49373713-G-C is described in ClinVar as Benign. ClinVar VariationId is 380823.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS1
Variant frequency is greater than expected in population nfe. GnomAd4 allele frequency = 0.0155 (2359/152282) while in subpopulation NFE AF = 0.0211 (1438/68014). AF 95% confidence interval is 0.0202. There are 19 homozygotes in GnomAd4. There are 1215 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High AC in GnomAd4 at 2359 AD gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004975.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
KCNB1
NM_004975.4
MANE Select
c.1847C>Gp.Thr616Ser
missense
Exon 2 of 2NP_004966.1Q14721

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
KCNB1
ENST00000371741.6
TSL:1 MANE Select
c.1847C>Gp.Thr616Ser
missense
Exon 2 of 2ENSP00000360806.3Q14721
KCNB1
ENST00000635465.1
TSL:1
c.1847C>Gp.Thr616Ser
missense
Exon 3 of 3ENSP00000489193.1Q14721
KCNB1
ENST00000635878.1
TSL:5
c.97-74330C>G
intron
N/AENSP00000489908.1A0A1B0GU02

Frequencies

GnomAD3 genomes
AF:
0.0155
AC:
2361
AN:
152164
Hom.:
19
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00357
Gnomad AMI
AF:
0.00439
Gnomad AMR
AF:
0.0128
Gnomad ASJ
AF:
0.0280
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.0193
Gnomad FIN
AF:
0.0329
Gnomad MID
AF:
0.0127
Gnomad NFE
AF:
0.0211
Gnomad OTH
AF:
0.0154
GnomAD2 exomes
AF:
0.0173
AC:
4347
AN:
250860
AF XY:
0.0183
show subpopulations
Gnomad AFR exome
AF:
0.00266
Gnomad AMR exome
AF:
0.00841
Gnomad ASJ exome
AF:
0.0290
Gnomad EAS exome
AF:
0.000163
Gnomad FIN exome
AF:
0.0365
Gnomad NFE exome
AF:
0.0197
Gnomad OTH exome
AF:
0.0162
GnomAD4 exome
AF:
0.0186
AC:
27151
AN:
1461882
Hom.:
309
Cov.:
33
AF XY:
0.0190
AC XY:
13810
AN XY:
727244
show subpopulations
African (AFR)
AF:
0.00236
AC:
79
AN:
33480
American (AMR)
AF:
0.00888
AC:
397
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.0275
AC:
719
AN:
26136
East Asian (EAS)
AF:
0.000101
AC:
4
AN:
39700
South Asian (SAS)
AF:
0.0206
AC:
1781
AN:
86258
European-Finnish (FIN)
AF:
0.0315
AC:
1682
AN:
53418
Middle Eastern (MID)
AF:
0.0179
AC:
103
AN:
5768
European-Non Finnish (NFE)
AF:
0.0191
AC:
21260
AN:
1112002
Other (OTH)
AF:
0.0186
AC:
1126
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.486
Heterozygous variant carriers
0
1669
3338
5006
6675
8344
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
798
1596
2394
3192
3990
<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:
0.0155
AC:
2359
AN:
152282
Hom.:
19
Cov.:
32
AF XY:
0.0163
AC XY:
1215
AN XY:
74462
show subpopulations
African (AFR)
AF:
0.00356
AC:
148
AN:
41558
American (AMR)
AF:
0.0127
AC:
195
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.0280
AC:
97
AN:
3468
East Asian (EAS)
AF:
0.000193
AC:
1
AN:
5184
South Asian (SAS)
AF:
0.0189
AC:
91
AN:
4822
European-Finnish (FIN)
AF:
0.0329
AC:
349
AN:
10618
Middle Eastern (MID)
AF:
0.0136
AC:
4
AN:
294
European-Non Finnish (NFE)
AF:
0.0211
AC:
1438
AN:
68014
Other (OTH)
AF:
0.0152
AC:
32
AN:
2106
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
113
226
339
452
565
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
28
56
84
112
140
<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:
0.0188
Hom.:
26
Bravo
AF:
0.0125
TwinsUK
AF:
0.0183
AC:
68
ALSPAC
AF:
0.0189
AC:
73
ESP6500AA
AF:
0.00386
AC:
17
ESP6500EA
AF:
0.0197
AC:
169
ExAC
AF:
0.0162
AC:
1969
Asia WGS
AF:
0.00577
AC:
20
AN:
3478
EpiCase
AF:
0.0208
EpiControl
AF:
0.0211

ClinVar

ClinVar submissions
Significance:Benign
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
-
2
not provided (2)
-
-
1
Developmental and epileptic encephalopathy, 26 (1)
-
-
1
not specified (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.074
BayesDel_addAF
Benign
-0.70
T
BayesDel_noAF
Benign
-0.76
CADD
Benign
16
DANN
Benign
0.28
DEOGEN2
Benign
0.20
T
Eigen
Benign
-0.64
Eigen_PC
Benign
-0.49
FATHMM_MKL
Benign
0.29
N
LIST_S2
Benign
0.28
T
MetaRNN
Benign
0.0023
T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
0.0
N
PhyloP100
5.0
PrimateAI
Benign
0.40
T
PROVEAN
Benign
0.44
N
REVEL
Benign
0.11
Sift
Benign
0.71
T
Sift4G
Benign
0.81
T
Polyphen
0.0
B
Vest4
0.047
MutPred
0.090
Gain of glycosylation at T616 (P = 0.0255)
MPC
0.17
ClinPred
0.0064
T
GERP RS
5.0
Varity_R
0.057
gMVP
0.18
Mutation Taster
=97/3
polymorphism (auto)

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: rs2229006; hg19: chr20-47990250; API