10-77637505-AGAGGAGGAGGAG-AGAGGAGGAGGAGGAGGAGGAG

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP3

The NM_001161352.2(KCNMA1):​c.129_137dupCTCCTCCTC​(p.Ser44_Ser46dup) variant causes a disruptive inframe insertion change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000509 in 1,572,864 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000049 ( 0 hom. )

Consequence

KCNMA1
NM_001161352.2 disruptive_inframe_insertion

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.55

Publications

2 publications found
Variant links:
Genes affected
KCNMA1 (HGNC:6284): (potassium calcium-activated channel subfamily M alpha 1) This gene encodes the alpha subunit of calcium-activated BK channel. The encoded protein is involved in several physiological processes including smooth muscle contraction, neurotransmitter release and neuronal excitability. Mutations in this gene are associated with a spectrum of neurological disorders including Paroxysmal Nonkinesigenic Dyskinesia 3, Idiopathic Generalized Epilepsy 16 and Liang-Wang syndrome. [provided by RefSeq, Aug 2022]
KCNMA1 Gene-Disease associations (from GenCC):
  • generalized epilepsy-paroxysmal dyskinesia syndrome
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Illumina, G2P, Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen
  • Liang-Wang syndrome
    Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
  • cerebellar atrophy, developmental delay, and seizures
    Inheritance: AR Classification: STRONG, MODERATE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

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

BP3
Nonframeshift variant in repetitive region in NM_001161352.2

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
KCNMA1NM_001161352.2 linkc.129_137dupCTCCTCCTC p.Ser44_Ser46dup disruptive_inframe_insertion Exon 1 of 28 ENST00000286628.14 NP_001154824.1 Q12791-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
KCNMA1ENST00000286628.14 linkc.129_137dupCTCCTCCTC p.Ser44_Ser46dup disruptive_inframe_insertion Exon 1 of 28 1 NM_001161352.2 ENSP00000286628.8 Q12791-1

Frequencies

GnomAD3 genomes
AF:
0.00000660
AC:
1
AN:
151442
Hom.:
0
Cov.:
33
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:
0.0000951
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000104
AC:
2
AN:
191788
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:
0.000142
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000492
AC:
7
AN:
1421422
Hom.:
0
Cov.:
27
AF XY:
0.00000425
AC XY:
3
AN XY:
705784
show subpopulations
African (AFR)
AF:
0.0000307
AC:
1
AN:
32584
American (AMR)
AF:
0.00
AC:
0
AN:
41604
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25564
East Asian (EAS)
AF:
0.0000785
AC:
3
AN:
38230
South Asian (SAS)
AF:
0.00
AC:
0
AN:
82954
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
51258
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5716
European-Non Finnish (NFE)
AF:
0.00000277
AC:
3
AN:
1084598
Other (OTH)
AF:
0.00
AC:
0
AN:
58914
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.411
Heterozygous variant carriers
0
1
2
4
5
6
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:
0.00000660
AC:
1
AN:
151442
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
73946
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41238
American (AMR)
AF:
0.00
AC:
0
AN:
15228
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3464
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5098
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4798
European-Finnish (FIN)
AF:
0.0000951
AC:
1
AN:
10512
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67808
Other (OTH)
AF:
0.00
AC:
0
AN:
2072
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.575
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Generalized epilepsy-paroxysmal dyskinesia syndrome Uncertain:1
Nov 23, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant has not been reported in the literature in individuals affected with KCNMA1-related conditions. ClinVar contains an entry for this variant (Variation ID: 935781). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant, c.129_137dup, results in the insertion of 3 amino acid(s) of the KCNMA1 protein (p.Ser58_Ser60dup), but otherwise preserves the integrity of the reading frame. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
PhyloP100
2.6
Mutation Taster
=79/21
polymorphism

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs572827902; hg19: chr10-79397263; API