12-2449107-G-C

Variant names:

• chr12-2449107-G-C
• rs1417477759
• NM_000719.7:c.609G>C

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_000719.7(CACNA1C):​c.609G>C​(p.Val203Val) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000718 in 1,393,194 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. V203V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 7.2e-7 (0 hom.)
• Consequence: CACNA1C NM_000719.7 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.92
• 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

ENSG00000285734 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.48).
• BP7: Synonymous conserved (PhyloP=2.92 with no splicing effect.

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.609G>C	p.Val203Val	synonymous	Exon 4 of 47	NP_000710.5
	CACNA1C	NM_001167623.2	MANE Plus Clinical	c.609G>C	p.Val203Val	synonymous	Exon 4 of 47	NP_001161095.1
	CACNA1C	NM_199460.4		c.609G>C	p.Val203Val	synonymous	Exon 4 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.609G>C	p.Val203Val	synonymous	Exon 4 of 47	ENSP00000382512.1
	CACNA1C	ENST00000399655.6	TSL:1 MANE Select	c.609G>C	p.Val203Val	synonymous	Exon 4 of 47	ENSP00000382563.1
	CACNA1C	ENST00000682544.1		c.699G>C	p.Val233Val	synonymous	Exon 4 of 50	ENSP00000507184.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 7.18e-7 AC: 1 AN: 1393194 Hom.: 0 Cov.: 30 AF XY: 0.00000146 AC XY: 1 AN XY: 686904

⚠️ 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: 31356

American (AMR) AF: 0.00 AC: 0 AN: 33396

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24836

East Asian (EAS) AF: 0.00 AC: 0 AN: 36928

South Asian (SAS) AF: 0.0000131 AC: 1 AN: 76226

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50044

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5634

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1076874

Other (OTH) AF: 0.00 AC: 0 AN: 57900

⚠️ 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
BayesDel_noAF	Benign	-0.48
CADD	Benign	11
DANN	Benign	0.80
PhyloP100		2.9

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: rs1417477759; hg19: chr12-2558273;