12-4911438-G-C

Variant summary

Our verdict is Benign. Variant got -10 ACMG points: 1P and 11B. PP2BP4_ModerateBP6BS1BS2

The NM_000217.3(KCNA1):​c.60G>C​(p.Gln20His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000434 in 1,613,612 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: š‘“ 0.00018 ( 0 hom., cov: 31)
Exomes š‘“: 0.00046 ( 1 hom. )

Consequence

KCNA1
NM_000217.3 missense

Scores

5
14

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:2

Conservation

PhyloP100: 1.51
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Benign. Variant got -10 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 episodic kinesigenic dyskinesia 1, episodic ataxia type 1, developmental and epileptic encephalopathy, isolated autosomal dominant hypomagnesemia, Glaudemans type.
BP4
Computational evidence support a benign effect (MetaRNN=0.13596153).
BP6
Variant 12-4911438-G-C is Benign according to our data. Variant chr12-4911438-G-C is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 447612.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=2}.
BS1
Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.000184 (28/152160) while in subpopulation NFE AF= 0.000368 (25/68022). AF 95% confidence interval is 0.000255. There are 0 homozygotes in gnomad4. There are 12 alleles in male gnomad4 subpopulation. Median coverage is 31. This position pass quality control queck.
BS2
High AC in GnomAd4 at 28 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNA1NM_000217.3 linkc.60G>C p.Gln20His 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.60G>C p.Gln20His missense_variant Exon 2 of 2 4 NM_000217.3 ENSP00000371985.3 Q09470

Frequencies

GnomAD3 genomes
AF:
0.000184
AC:
28
AN:
152160
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.0000724
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:
0.000368
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000113
AC:
28
AN:
248316
Hom.:
0
AF XY:
0.0000963
AC XY:
13
AN XY:
134938
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 SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.000241
Gnomad OTH exome
AF:
0.000165
GnomAD4 exome
AF:
0.000460
AC:
672
AN:
1461452
Hom.:
1
Cov.:
35
AF XY:
0.000444
AC XY:
323
AN XY:
727072
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000232
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.000581
Gnomad4 OTH exome
AF:
0.000397
GnomAD4 genome
AF:
0.000184
AC:
28
AN:
152160
Hom.:
0
Cov.:
31
AF XY:
0.000161
AC XY:
12
AN XY:
74332
show subpopulations
Gnomad4 AFR
AF:
0.0000724
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:
0.000368
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000225
Hom.:
0
Bravo
AF:
0.000170
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000519
AC:
2
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.000107
AC:
13
EpiCase
AF:
0.000491
EpiControl
AF:
0.000474

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Episodic ataxia type 1 Uncertain:1Benign:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Oct 31, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Uncertain:1Benign:1
Aug 01, 2024
CeGaT Center for Human Genetics Tuebingen
Significance: Likely benign
Review Status: criteria provided, single submitter
Collection Method: clinical testing

KCNA1: PP2, BS2 -

Aug 03, 2018
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
0.11
BayesDel_addAF
Benign
-0.13
T
BayesDel_noAF
Benign
-0.10
CADD
Benign
20
DANN
Benign
0.93
DEOGEN2
Benign
0.41
T
Eigen
Benign
-0.17
Eigen_PC
Benign
-0.066
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.85
T
M_CAP
Uncertain
0.12
D
MetaRNN
Benign
0.14
T
MetaSVM
Uncertain
0.46
D
MutationAssessor
Benign
2.0
M
PrimateAI
Uncertain
0.62
T
PROVEAN
Benign
-1.0
N
REVEL
Uncertain
0.38
Sift
Benign
0.24
T
Sift4G
Benign
0.20
T
Polyphen
0.010
B
Vest4
0.23
MutPred
0.27
Gain of catalytic residue at Y24 (P = 0.0028);
MVP
0.91
MPC
1.1
ClinPred
0.056
T
GERP RS
2.8
Varity_R
0.12
gMVP
0.72

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs201504073; hg19: chr12-5020604; COSMIC: COSV66838441; COSMIC: COSV66838441; API