rs1556109769

Positions:

• chr12-2679597-G-A

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 1P and 5B. PP2 BP4 BS2

The NM_000719.7(CACNA1C):​c.5245G>A​(p.Val1749Met) variant causes a missense change. The variant allele was found at a frequency of 0.0000171 in 1,461,452 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.000017 (0 hom.)
• Consequence: CACNA1C NM_000719.7 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.94

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

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), CACNA1C. . Gene score misZ 6.4654 (greater than the threshold 3.09). Trascript score misZ 7.2674 (greater than threshold 3.09). GenCC has associacion of gene with intellectual disability, neurodevelopmental disorder with hypotonia, language delay, and skeletal defects with or without seizures, Brugada syndrome, long QT syndrome, short QT syndrome, long qt syndrome 8, Timothy syndrome, Brugada syndrome 3.
• BP4: Computational evidence support a benign effect (MetaRNN=0.29270276).
• BS2: High AC in GnomAdExome4 at 25 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CACNA1C	NM_000719.7	c.5245G>A	p.Val1749Met	missense_variant	42/47	ENST00000399655.6	NP_000710.5
CACNA1C	NM_001167623.2	c.5245G>A	p.Val1749Met	missense_variant	42/47	ENST00000399603.6	NP_001161095.1
CACNA1C-AS1	NR_045725.1	n.334-1700C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CACNA1C	ENST00000399603.6	c.5245G>A	p.Val1749Met	missense_variant	42/47	5	NM_001167623.2	ENSP00000382512
CACNA1C	ENST00000399655.6	c.5245G>A	p.Val1749Met	missense_variant	42/47	1	NM_000719.7	ENSP00000382563
CACNA1C-AS1	ENST00000501371.5	n.295-1700C>T		intron_variant, non_coding_transcript_variant		2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.0000171 AC: 25 AN: 1461452 Hom.: 0 Cov.: 31 AF XY: 0.0000179 AC XY: 13 AN XY: 727002

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: 0.0000225

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

CACNA1C-related disorder Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Jul 31, 2023

The CACNA1C c.5245G>A variant is predicted to result in the amino acid substitution p.Val1749Met. To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Long QT syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 14, 2020

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with CACNA1C-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces valine with methionine at codon 1749 of the CACNA1C protein (p.Val1749Met). The valine residue is moderately conserved and there is a small physicochemical difference between valine and methionine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.086	D
BayesDel_noAF	Benign	-0.11
CADD	Uncertain	25
DANN	Benign	0.95
DEOGEN2	Benign	0.0053	T;.;.;.;.;.;.;.;.;.;.;.;.;.;.;T;.;.;.;.;T;.;T
Eigen	Benign	0.00014
Eigen_PC	Benign	0.092
FATHMM_MKL	Uncertain	0.94	D
M_CAP	Uncertain	0.22	D
MetaRNN	Benign	0.29	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Uncertain	0.69	D
MutationAssessor	Benign	1.4	.;.;.;.;.;.;.;.;.;.;L;.;.;.;.;.;.;.;.;.;.;.;.
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
PrimateAI	Uncertain	0.75	T
PROVEAN	Benign	-0.57	N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;N;.
REVEL	Uncertain	0.36
Sift	Benign	0.23	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;.
Sift4G	Benign	0.23	T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T;T
Polyphen		0.38, 0.82, 0.049, 0.11, 0.11, 0.63, 0.49, 0.087, 0.49, 0.53, 1.0	.;B;P;B;B;B;P;P;B;B;P;P;P;D;P;.;P;P;.;.;.;B;.
Vest4		0.28
MutPred		0.21		.;.;.;.;.;.;.;.;.;.;Gain of phosphorylation at T1802 (P = 0.0806);.;.;.;.;.;.;.;.;.;.;.;.;
MVP		0.79
MPC		0.65
ClinPred		0.85	D
GERP RS		4.6
gMVP		0.46

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs1556109769; hg19: chr12-2788763;