rs1553729735

Variant names:

• chr3-50379152-C-T
• rs1553729735
• NM_006030.4:c.1200G>A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_006030.4(CACNA2D2):​c.1200G>A​(p.Thr400Thr) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,708 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: 6.8e-7 (0 hom.)
• Consequence: CACNA2D2 NM_006030.4 synonymous
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.00200

Genes affected

CACNA2D2 (HGNC:1400): (calcium voltage-gated channel auxiliary subunit alpha2delta 2) Calcium channels mediate the entry of calcium ions into the cell upon membrane polarization. This gene encodes the alpha-2/delta subunit of the voltage-dependent calcium channel complex. The complex consists of the main channel-forming subunit alpha-1, and auxiliary subunits alpha-2/delta, beta, and gamma. The auxiliary subunits function in the assembly and membrane localization of the complex, and modulate calcium currents and channel activation/inactivation kinetics. The subunit encoded by this gene undergoes post-translational cleavage to yield the extracellular alpha2 peptide and a membrane-anchored delta polypeptide. This subunit is a receptor for the antiepileptic drug, gabapentin. Mutations in this gene are associated with early infantile epileptic encephalopathy. Single nucleotide polymorphisms in this gene are correlated with increased sensitivity to opioid drugs. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Mar 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CACNA2D2	NM_006030.4	c.1200G>A	p.Thr400Thr	synonymous_variant	Exon 12 of 38	ENST00000424201.7	NP_006021.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CACNA2D2	ENST00000424201.7	c.1200G>A	p.Thr400Thr	synonymous_variant	Exon 12 of 38	1	NM_006030.4	ENSP00000390329.2
CACNA2D2	ENST00000423994.6	c.1200G>A	p.Thr400Thr	synonymous_variant	Exon 12 of 39	5		ENSP00000407393.2
CACNA2D2	ENST00000266039.7	c.1200G>A	p.Thr400Thr	synonymous_variant	Exon 12 of 38	1		ENSP00000266039.3
CACNA2D2	ENST00000360963.7	c.993G>A	p.Thr331Thr	synonymous_variant	Exon 12 of 38	1		ENSP00000354228.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461708 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727126

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: 8.99e-7

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

Early infantile epileptic encephalopathy with suppression bursts Uncertain:1

Apr 12, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects codon 400 of the CACNA2D2 mRNA. It is a 'silent' change, meaning that it does not change the encoded amino acid sequence of the CACNA2D2 protein. This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CACNA2D2-related conditions. ClinVar contains an entry for this variant (Variation ID: 530515). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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. -

not provided Uncertain:1

Aug 01, 2019

CeGaT Center for Human Genetics Tuebingen

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.28
CADD	Uncertain	24
DANN	Benign	0.64

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.79		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.79		Position offset: -2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1553729735; hg19: chr3-50416583; COSMIC: COSV56561396;