NM_000719.7:c.1031C>A

Variant names:

• chr12-2493304-C-A
• rs200935321
• NM_000719.7:c.1031C>A

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_000719.7(CACNA1C):​c.1031C>A​(p.Thr344Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,792 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T344I) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CACNA1C NM_000719.7 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.91
• 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: ClinGen, Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics, Orphanet
• 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: ClinGen, Orphanet
• 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: ClinGen, Ambry Genetics

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.935

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNA1C	NM_000719.7	MANE Select	c.1031C>A	p.Thr344Asn	missense	Exon 7 of 47	NP_000710.5
	CACNA1C	NM_001167623.2	MANE Plus Clinical	c.1031C>A	p.Thr344Asn	missense	Exon 7 of 47	NP_001161095.1	Q13936-37
	CACNA1C	NM_199460.4		c.1031C>A	p.Thr344Asn	missense	Exon 7 of 50	NP_955630.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNA1C	ENST00000399603.6	TSL:5 MANE Plus Clinical	c.1031C>A	p.Thr344Asn	missense	Exon 7 of 47	ENSP00000382512.1	Q13936-37
	CACNA1C	ENST00000399655.6	TSL:1 MANE Select	c.1031C>A	p.Thr344Asn	missense	Exon 7 of 47	ENSP00000382563.1	Q13936-12
	CACNA1C	ENST00000682544.1		c.1121C>A	p.Thr374Asn	missense	Exon 7 of 50	ENSP00000507184.1	A0A804HIR0

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461792 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727186

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111934

Other (OTH) AF: 0.00 AC: 0 AN: 60382

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
CardioboostArm	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.14
CADD	Pathogenic	27
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.72	D
Eigen	Pathogenic	0.88
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Pathogenic	0.91	D
MetaRNN	Pathogenic	0.94	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.7	M
PhyloP100		7.9
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-4.5	D
REVEL	Pathogenic	0.91
Sift	Uncertain	0.016	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.61		Gain of catalytic residue at P339 (P = 0.0027)
MVP		0.95
MPC		2.4
ClinPred		0.99	D
GERP RS		5.1
gMVP		0.99
Mutation Taster		=4/96	disease causing

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: rs200935321; hg19: chr12-2602470;