chr20-49373240-G-T

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 1P and 7B. PP2BP4_ModerateBP6BS2

The NM_004975.4(KCNB1):​c.2320C>A​(p.Pro774Thr) variant causes a missense change. The variant allele was found at a frequency of 0.00000496 in 1,614,026 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. P774P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

KCNB1
NM_004975.4 missense

Scores

10
9

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:1

Conservation

PhyloP100: 5.00
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

PP2
Missense variant in gene, where missense usually causes diseases (based on misZ statistic), KCNB1. . Gene score misZ 4.269 (greater than the threshold 3.09). Trascript score misZ 5.3923 (greater than threshold 3.09). GenCC has associacion of gene with undetermined early-onset epileptic encephalopathy, complex neurodevelopmental disorder, developmental and epileptic encephalopathy, 26.
BP4
Computational evidence support a benign effect (MetaRNN=0.22212937).
BP6
Variant 20-49373240-G-T is Benign according to our data. Variant chr20-49373240-G-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 568166.We mark this variant Likely_benign, oryginal submissions are: {Benign=1, Uncertain_significance=1}.
BS2
High AC in GnomAdExome4 at 6 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
KCNB1NM_004975.4 linkuse as main transcriptc.2320C>A p.Pro774Thr missense_variant 2/2 ENST00000371741.6
LOC105372649XR_001754659.2 linkuse as main transcriptn.1201+41216G>T intron_variant, non_coding_transcript_variant
KCNB1XM_011528799.3 linkuse as main transcriptc.2320C>A p.Pro774Thr missense_variant 3/3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
KCNB1ENST00000371741.6 linkuse as main transcriptc.2320C>A p.Pro774Thr missense_variant 2/21 NM_004975.4 P1
KCNB1ENST00000635465.1 linkuse as main transcriptc.2320C>A p.Pro774Thr missense_variant 3/31 P1
ENST00000637341.1 linkuse as main transcriptn.206+41216G>T intron_variant, non_coding_transcript_variant 5
KCNB1ENST00000635878.1 linkuse as main transcriptc.97-73857C>A intron_variant 5

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152134
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000796
AC:
2
AN:
251374
Hom.:
0
AF XY:
0.00000736
AC XY:
1
AN XY:
135852
show subpopulations
Gnomad AFR exome
AF:
0.0000616
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS 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:
0.00000410
AC:
6
AN:
1461892
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
727248
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000447
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000504
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000180
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152134
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74312
show subpopulations
Gnomad4 AFR
AF:
0.0000483
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000189
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenApr 01, 2023KCNB1: PP2 -
Developmental and epileptic encephalopathy, 26 Benign:1
Benign, criteria provided, single submitterclinical testingInvitaeMay 13, 2023- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.064
BayesDel_addAF
Benign
-0.0071
T
BayesDel_noAF
Uncertain
-0.070
CADD
Benign
22
DANN
Uncertain
0.99
DEOGEN2
Benign
0.34
T;T
Eigen
Uncertain
0.37
Eigen_PC
Uncertain
0.45
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Benign
0.78
.;T
M_CAP
Benign
0.049
D
MetaRNN
Benign
0.22
T;T
MetaSVM
Uncertain
0.75
D
MutationAssessor
Benign
0.81
L;L
MutationTaster
Benign
1.0
D
PrimateAI
Uncertain
0.60
T
PROVEAN
Benign
-1.1
N;.
REVEL
Uncertain
0.30
Sift
Uncertain
0.0080
D;.
Sift4G
Uncertain
0.059
T;T
Polyphen
0.77
P;P
Vest4
0.25
MutPred
0.18
Gain of phosphorylation at P774 (P = 0.0124);Gain of phosphorylation at P774 (P = 0.0124);
MVP
0.48
MPC
0.34
ClinPred
0.33
T
GERP RS
4.5
Varity_R
0.16
gMVP
0.49

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs748597382; hg19: chr20-47989777; API