rs1555192348

Variant names:

• chr12-2115251-C-T
• rs1555192348
• NM_000719.7:c.77C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000719.7(CACNA1C):​c.77C>T​(p.Ala26Val) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. A26T) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 34)
• Consequence: CACNA1C NM_000719.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.74
• Publications: 0 publications found

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 Gene-Disease associations (from GenCC):

• Timothy syndrome

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
• neurodevelopmental disorder with hypotonia, language delay, and skeletal defects with or without seizures

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics
• long QT syndrome

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• long QT syndrome 8

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• Brugada syndrome

  Inheritance: AD Classification: SUPPORTIVE, NO_KNOWN Submitted by: Orphanet, ClinGen
• Brugada syndrome 3

  Inheritance: AD Classification: LIMITED, NO_KNOWN Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• intellectual disability

  Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics
• short QT syndrome

  Inheritance: AD Classification: LIMITED, NO_KNOWN Submitted by: Ambry Genetics, ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000719.7. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNA1C	NM_000719.7	MANE Select	c.77C>T	p.Ala26Val	missense	Exon 2 of 47	NP_000710.5
	CACNA1C	NM_001167623.2	MANE Plus Clinical	c.77C>T	p.Ala26Val	missense	Exon 2 of 47	NP_001161095.1
	CACNA1C	NM_199460.4		c.77C>T	p.Ala26Val	missense	Exon 2 of 50	NP_955630.3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNA1C	ENST00000399603.6	TSL:5 MANE Plus Clinical	c.77C>T	p.Ala26Val	missense	Exon 2 of 47	ENSP00000382512.1
	CACNA1C	ENST00000399655.6	TSL:1 MANE Select	c.77C>T	p.Ala26Val	missense	Exon 2 of 47	ENSP00000382563.1
	CACNA1C	ENST00000682544.1		c.167C>T	p.Ala56Val	missense	Exon 2 of 50	ENSP00000507184.1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 34

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Long QT syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.12
CardioboostArm	Benign	0.000058
BayesDel_addAF	Pathogenic	0.17	D
BayesDel_noAF	Uncertain	0.010
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.010	T
Eigen	Uncertain	0.22
Eigen_PC	Uncertain	0.34
FATHMM_MKL	Uncertain	0.94	D
M_CAP	Benign	0.046	D
MetaRNN	Uncertain	0.46	T
MetaSVM	Pathogenic	0.88	D
MutationAssessor	Benign	0.0	N
PhyloP100		3.7
PrimateAI	Uncertain	0.72	T
PROVEAN	Uncertain	-3.0	D
REVEL	Uncertain	0.45
Sift	Uncertain	0.0030	D
Sift4G	Uncertain	0.058	T
Polyphen		0.62	P
Vest4		0.31
MutPred		0.36		Gain of catalytic residue at A26 (P = 0)
MVP		0.88
MPC		1.5
ClinPred		0.86	D
GERP RS		5.8
PromoterAI		-0.0060	Neutral
gMVP		0.63
Mutation Taster		=54/46	polymorphism

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

Other links and lift over

dbSNP: rs1555192348; hg19: chr12-2224417;