12-2691106-C-CG

Position:

chr12-2691106-C-CG

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PVS1_ModerateBS2

The ENST00000399655.6(CACNA1C):c.6329dup(p.Glu2111ArgfsTer15) variant causes a frameshift change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000391 in 1,611,816 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. A2108A) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.000040 ( 0 hom. )

Consequence

CACNA1C
ENST00000399655.6 frameshift

Scores

Not classified

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 7.70

Variant links:

Genes affected

CACNA1C (HGNC:1390): (calcium voltage-gated channel subunit alpha1 C) This gene encodes an alpha-1 subunit of a voltage-dependent calcium channel. Calcium channels mediate the influx of calcium ions into the cell upon membrane polarization. The alpha-1 subunit consists of 24 transmembrane segments and forms the pore through which ions pass into the cell. The calcium channel consists of a complex of alpha-1, alpha-2/delta, beta, and gamma subunits in a 1:1:1:1 ratio. There are multiple isoforms of each of these proteins, either encoded by different genes or the result of alternative splicing of transcripts. The protein encoded by this gene binds to and is inhibited by dihydropyridine. Alternative splicing results in many transcript variants encoding different proteins. Some of the predicted proteins may not produce functional ion channel subunits. [provided by RefSeq, Oct 2012]

CACNA1C links:

CACNA1C-AS1 (HGNC:40119): (CACNA1C antisense RNA 1)

CACNA1C-AS1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -2 ACMG points.

PVS1

Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.0145 CDS is truncated, and there are 0 pathogenic variants in the truncated region.

BS2

High AC in GnomAdExome4 at 59 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
CACNA1C	NM_000719.7 linkuse as main transcript	c.6329dup	p.Glu2111ArgfsTer15	frameshift_variant	47/47	ENST00000399655.6	NP_000710.5
CACNA1C	NM_001167623.2 linkuse as main transcript	c.6329dup	p.Glu2111ArgfsTer15	frameshift_variant	47/47	ENST00000399603.6	NP_001161095.1
CACNA1C-AS1	NR_045725.1 linkuse as main transcript	n.51_52insC		non_coding_transcript_exon_variant	1/4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
CACNA1C	ENST00000399603.6 linkuse as main transcript	c.6329dup	p.Glu2111ArgfsTer15	frameshift_variant	47/47	5	NM_001167623.2	ENSP00000382512	Q13936-37
CACNA1C	ENST00000399655.6 linkuse as main transcript	c.6329dup	p.Glu2111ArgfsTer15	frameshift_variant	47/47	1	NM_000719.7	ENSP00000382563	Q13936-12
CACNA1C-AS1	ENST00000501371.5 linkuse as main transcript	n.12_13insC		non_coding_transcript_exon_variant	1/4	2

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

151980

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:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000588

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000820

AC:

AN:

244018

Hom.:

AF XY:

0.00

AC XY:

AN XY:

133264

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:

0.0000182

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000404

AC:

AN:

1459836

Hom.:

Cov.:

AF XY:

0.0000344

AC XY:

AN XY:

725994

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:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000486

Gnomad4 OTH exome

AF:

0.0000830

GnomAD4 genome

AF:

0.0000263

AC:

AN:

151980

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74226

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:

0.00

Gnomad4 NFE

AF:

0.0000588

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000712

Hom.:

Bravo

AF:

0.0000113

EpiCase

AF:

0.0000545

EpiControl

AF:

0.0000594

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Apr 25, 2016

Variant identified in a genome or exome case(s) and assessed due to predicted null impact of the variant or pathogenic assertions in the literature or databases. Disclaimer: This variant has not undergone full assessment. The following are preliminary notes: LOF not a known disease mechanism for CACNA1C ; ExAC: 2/57170 European chromosomes -

Timothy syndrome;C2678478:Brugada syndrome 3;CN260585:Long qt syndrome 8

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 17, 2021

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

AiLife Diagnostics, AiLife Diagnostics

Nov 21, 2021

- -

Long QT syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 11, 2024

This sequence change creates a premature translational stop signal (p.Glu2111Argfs*15) in the CACNA1C gene. While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 28 amino acid(s) of the CACNA1C protein. This variant is present in population databases (rs771708175, gnomAD 0.004%). This variant has not been reported in the literature in individuals affected with CACNA1C-related conditions. ClinVar contains an entry for this variant (Variation ID: 190695). 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. -

Cardiovascular phenotype

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 14, 2023

The c.6329dupG variant, located in coding exon 47 of the CACNA1C gene, results from a duplication of G at nucleotide position 6329, causing a translational frameshift with a predicted alternate stop codon (p.E2111Rfs*15). This alteration occurs at the 3' terminus of theCACNA1C gene, is not expected to trigger nonsense-mediated mRNAdecay, and only impacts the last 1% of the protein. The exact functional effect of this alteration is unknown. According to data from gnomAD, the frequency for this variant is above the maximum credible frequency for a cardiac disease-causing variant in this gene based on internally established thresholds (Karczewski et al. Nature. 2020 May;581(7809):434-443; Whiffin et al. Genet Med. 2017 10;19:1151-1158). Based on the supporting evidence, the association of this alteration with CACNA1C-related neurodevelopmental disorder is unknown; however, the association with CACNA1C-related Timothy syndrome or long QT syndrome is unlikely. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

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.

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