19-13286794-C-T

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 1P and 2B. PP2BP4_Moderate

The NM_001127222.2(CACNA1A):c.3262G>A(p.Ala1088Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,612,650 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A1088S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

CACNA1A
NM_001127222.2 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: -0.915

Variant links:

Genes affected

CACNA1A (HGNC:1388): (calcium voltage-gated channel subunit alpha1 A) Voltage-dependent calcium channels mediate the entry of calcium ions into excitable cells, and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, and gene expression. Calcium channels are multisubunit complexes composed of alpha-1, beta, alpha-2/delta, and gamma subunits. The channel activity is directed by the pore-forming alpha-1 subunit, whereas, the others act as auxiliary subunits regulating this activity. The distinctive properties of the calcium channel types are related primarily to the expression of a variety of alpha-1 isoforms, alpha-1A, B, C, D, E, and S. This gene encodes the alpha-1A subunit, which is predominantly expressed in neuronal tissue. Mutations in this gene are associated with 2 neurologic disorders, familial hemiplegic migraine and episodic ataxia 2. This gene also exhibits polymorphic variation due to (CAG)n-repeats. Multiple transcript variants encoding different isoforms have been found for this gene. In one set of transcript variants, the (CAG)n-repeats occur in the 3' UTR, and are not associated with any disease. But in another set of variants, an insertion extends the coding region to include the (CAG)n-repeats which encode a polyglutamine tract. Expansion of the (CAG)n-repeats from the normal 4-18 to 21-33 in the coding region is associated with spinocerebellar ataxia 6. [provided by RefSeq, Jul 2016]

CACNA1A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PP2

Missense variant where missense usually causes diseases, CACNA1A

BP4

Computational evidence support a benign effect (MetaRNN=0.07427722).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CACNA1A	NM_001127222.2 linkuse as main transcript	c.3262G>A	p.Ala1088Thr	missense_variant	20/47	ENST00000360228.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CACNA1A	ENST00000360228.11 linkuse as main transcript	c.3262G>A	p.Ala1088Thr	missense_variant	20/47	1	NM_001127222.2		O00555-8

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151992

Hom.:

Cov.:

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:

0.0000945

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000164

AC:

AN:

243198

Hom.:

AF XY:

0.0000151

AC XY:

AN XY:

132874

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:

0.0000365

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000110

AC:

AN:

1460658

Hom.:

Cov.:

AF XY:

0.0000124

AC XY:

AN XY:

726648

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.0000755

Gnomad4 NFE exome

AF:

0.00000810

Gnomad4 OTH exome

AF:

0.0000332

GnomAD4 genome

AF:

0.0000132

AC:

AN:

151992

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74236

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.0000945

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000451

Hom.:

Bravo

AF:

0.00000756

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000122

AC:

ExAC

AF:

0.0000249

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Episodic ataxia type 2;C4310716:Developmental and epileptic encephalopathy, 42

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 20, 2023

This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 1089 of the CACNA1A protein (p.Ala1089Thr). 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 has not been reported in the literature in individuals affected with CACNA1A-related conditions. ClinVar contains an entry for this variant (Variation ID: 476251). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CACNA1A protein function. 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. -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

May 15, 2018

The p.A1089T variant (also known as c.3265G>A), located in coding exon 20 of the CACNA1A gene, results from a G to A substitution at nucleotide position 3265. The alanine at codon 1089 is replaced by threonine, an amino acid with similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.066

BayesDel_addAF

Benign

-0.098

BayesDel_noAF

Benign

-0.38

Cadd

Benign

0.011

Dann

Benign

0.75

Eigen

Benign

-2.0

Eigen_PC

Benign

-2.0

FATHMM_MKL

Benign

0.028

LIST_S2

Benign

0.50

T;T;T;T;T;T;T;T;.;T;T;T;T;T;T

M_CAP

Pathogenic

0.30

MetaRNN

Benign

0.074

T;T;T;T;T;T;T;T;T;T;T;T;T;T;T

MetaSVM

Uncertain

-0.16

MutationTaster

Benign

1.0

N;N;N

PrimateAI

Benign

0.34

Sift4G

Benign

0.71

T;T;.;.;.;.;.;.;.;.;.;.;.;.;.

Vest4

0.14

MVP

0.65

MPC

0.013

ClinPred

0.039

GERP RS

-10

Varity_R

0.024

gMVP

0.50

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over