rs1555884489

chr12-2608552-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_000719.7(CACNA1C):c.3398G>A(p.Gly1133Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/20 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. G1133G) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CACNA1C NM_000719.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.60

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 7 ACMG points.

• PM1: In a region_of_interest Dihydropyridine binding (size 89) in uniprot entity CAC1C_HUMAN there are 10 pathogenic changes around while only 3 benign (77%) in NM_000719.7
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, CACNA1C
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.909

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CACNA1C	NM_000719.7	c.3398G>A	p.Gly1133Asp	missense_variant	27/47	ENST00000399655.6
CACNA1C	NM_001167623.2	c.3398G>A	p.Gly1133Asp	missense_variant	27/47	ENST00000399603.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CACNA1C	ENST00000399603.6	c.3398G>A	p.Gly1133Asp	missense_variant	27/47	5	NM_001167623.2
CACNA1C	ENST00000399655.6	c.3398G>A	p.Gly1133Asp	missense_variant	27/47	1	NM_000719.7

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Long QT syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 25, 2017

This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with CACNA1C-related disease. 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. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This sequence change replaces glycine with aspartic acid at codon 1133 of the CACNA1C protein (p.Gly1133Asp). The glycine residue is highly conserved and there is a moderate physicochemical difference between glycine and aspartic acid. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
CardioboostArm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
Cadd	Pathogenic	29
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.70	D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;T;.;.;.;.;T;.;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.91	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
PrimateAI	Pathogenic	0.91	D
PROVEAN	Pathogenic	-6.6	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0010	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.
Sift4G	Pathogenic	0.0	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
Polyphen		1.0	.;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;.;D;D;.;.;.;D;.
Vest4		0.91
MutPred		0.54		.;.;.;.;.;.;.;.;.;.;.;Gain of catalytic residue at N1157 (P = 0.0424);Gain of catalytic residue at N1157 (P = 0.0424);.;.;.;.;.;.;.;.;.;.;.;
MVP		0.97
MPC		2.5
ClinPred		1.0	D
GERP RS		4.7
gMVP		0.99

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: rs1555884489; hg19: chr12-2717718; COSMIC: COSV59748429; COSMIC: COSV59748429;