12-4911390-G-T

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_000217.3(KCNA1):​c.12G>T​(p.Met4Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000149 in 1,612,388 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

KCNA1
NM_000217.3 missense

Scores

5
14

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.13

Publications

1 publications found
Variant links:
Genes affected
KCNA1 (HGNC:6218): (potassium voltage-gated channel subfamily A member 1) This gene encodes a voltage-gated delayed potassium channel that is phylogenetically related to the Drosophila Shaker channel. The encoded protein has six putative transmembrane segments (S1-S6), and the loop between S5 and S6 forms the pore and contains the conserved selectivity filter motif (GYGD). The functional channel is a homotetramer. The N-terminus of the channel is associated with beta subunits that can modify the inactivation properties of the channel as well as affect expression levels. The C-terminus of the channel is complexed to a PDZ domain protein that is responsible for channel targeting. Mutations in this gene have been associated with myokymia with periodic ataxia (AEMK). [provided by RefSeq, Jul 2008]
KCNA1 Gene-Disease associations (from GenCC):
  • episodic ataxia type 1
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, ClinGen, Orphanet, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
  • episodic kinesigenic dyskinesia 1
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • isolated autosomal dominant hypomagnesemia, Glaudemans type
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • genetic developmental and epileptic encephalopathy
    Inheritance: AR, AD Classification: SUPPORTIVE, LIMITED Submitted by: G2P, Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -1 ACMG points.

PP2
Missense variant in the KCNA1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 33 curated pathogenic missense variants (we use a threshold of 10). The gene has 3 curated benign missense variants. Gene score misZ: 3.3255 (above the threshold of 3.09). Trascript score misZ: 3.8671 (above the threshold of 3.09). GenCC associations: The gene is linked to isolated autosomal dominant hypomagnesemia, Glaudemans type, episodic ataxia type 1, genetic developmental and epileptic encephalopathy, episodic kinesigenic dyskinesia 1.
BP4
Computational evidence support a benign effect (MetaRNN=0.18973646).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNA1NM_000217.3 linkc.12G>T p.Met4Ile missense_variant Exon 2 of 2 ENST00000382545.5 NP_000208.2 Q09470

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNA1ENST00000382545.5 linkc.12G>T p.Met4Ile missense_variant Exon 2 of 2 4 NM_000217.3 ENSP00000371985.3 Q09470

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
151866
Hom.:
0
Cov.:
31
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000820
AC:
2
AN:
243928
AF XY:
0.00
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:
0.0000183
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000157
AC:
23
AN:
1460522
Hom.:
0
Cov.:
35
AF XY:
0.0000124
AC XY:
9
AN XY:
726610
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.00
AC:
0
AN:
44700
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86226
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52544
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5616
European-Non Finnish (NFE)
AF:
0.0000180
AC:
20
AN:
1111838
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60328
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.462
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.00000658
AC:
1
AN:
151866
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74148
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41336
American (AMR)
AF:
0.00
AC:
0
AN:
15264
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5134
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4788
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10594
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67964
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.0000712
Hom.:
0
Bravo
AF:
0.00000378
ExAC
AF:
0.0000166
AC:
2

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Oct 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

KCNA1: PP2 -

Dec 20, 2019
Athena Diagnostics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.13
BayesDel_addAF
Uncertain
0.068
T
BayesDel_noAF
Benign
-0.12
CADD
Benign
20
DANN
Benign
0.96
DEOGEN2
Benign
0.30
T
Eigen
Benign
-0.29
Eigen_PC
Benign
-0.13
FATHMM_MKL
Uncertain
0.89
D
LIST_S2
Benign
0.78
T
M_CAP
Uncertain
0.12
D
MetaRNN
Benign
0.19
T
MetaSVM
Uncertain
0.17
D
MutationAssessor
Benign
1.2
L
PhyloP100
1.1
PrimateAI
Uncertain
0.65
T
PROVEAN
Benign
-0.14
N
REVEL
Benign
0.27
Sift
Benign
0.63
T
Sift4G
Benign
0.22
T
Polyphen
0.0
B
Vest4
0.28
MutPred
0.29
Gain of catalytic residue at M4 (P = 0.0025);
MVP
0.86
MPC
1.3
ClinPred
0.12
T
GERP RS
3.6
Varity_R
0.30
gMVP
0.36
Mutation Taster
=92/8
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: rs773128496; hg19: chr12-5020556; API