10-77403988-C-T

Variant summary

Our verdict is Benign. Variant got -10 ACMG points: 0P and 10B. BP4_Strong BP6 BP7 BS1

The NM_001161352.2(KCNMA1):c.414G>A(p.Ala138=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000663 in 1,614,148 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.00021 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000051 (1 hom.)
• Consequence: KCNMA1 NM_001161352.2 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:2
• Conservation: PhyloP100: -2.96

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]

ACMG classification

Verdict is Benign. Variant got -10 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.6).
• BP6: Variant 10-77403988-C-T is Benign according to our data. Variant chr10-77403988-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 464300.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=1}.
• BP7: Synonymous conserved (PhyloP=-2.96 with no splicing effect.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00021 (32/152290) while in subpopulation AFR AF= 0.000698 (29/41568). AF 95% confidence interval is 0.000498. There are 0 homozygotes in gnomad4. There are 18 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNMA1	NM_001161352.2	c.414G>A	p.Ala138=	synonymous_variant	2/28	ENST00000286628.14

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNMA1	ENST00000286628.14	c.414G>A	p.Ala138=	synonymous_variant	2/28	1	NM_001161352.2	A2

Frequencies

GnomAD3 genomes AF: 0.000210 AC: 32 AN: 152172 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000700

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000294

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000954 AC: 24 AN: 251442 Hom.: 0 AF XY: 0.0000883 AC XY: 12 AN XY: 135888

Gnomad AFR exome AF: 0.000308

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000707

Gnomad SAS exome AF: 0.0000653

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000352

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000513 AC: 75 AN: 1461858 Hom.: 1 Cov.: 32 AF XY: 0.0000509 AC XY: 37 AN XY: 727230

Gnomad4 AFR exome AF: 0.000747

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000126

Gnomad4 SAS exome AF: 0.0000580

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000216

Gnomad4 OTH exome AF: 0.000215

GnomAD4 genome AF: 0.000210 AC: 32 AN: 152290 Hom.: 0 Cov.: 32 AF XY: 0.000242 AC XY: 18 AN XY: 74460

Gnomad4 AFR AF: 0.000698

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000194

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000294

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000127 Hom.: 0

Bravo AF: 0.000166

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Uncertain:1 Benign:1

Likely benign, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Apr 01, 2022	KCNMA1: BP4, BP7 -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	May 25, 2018	- -

Generalized epilepsy-paroxysmal dyskinesia syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Dec 19, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.60
Cadd	Benign	6.2
Dann	Benign	0.71

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

Other links and lift over

dbSNP: rs61736948; hg19: chr10-79163746;