rs773966897

chr16-1205268-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_021098.3(CACNA1H):c.2603+3G>A variant causes a splice donor region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000138 in 1,449,802 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: 0.0000014 (0 hom.)
• Consequence: CACNA1H NM_021098.3 splice_donor_region, intron
• Scores: Splicing: ADA: 0.00006001
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.570

Genes affected

CACNA1H (HGNC:1395): (calcium voltage-gated channel subunit alpha1 H) This gene encodes a T-type member of the alpha-1 subunit family, a protein in the voltage-dependent calcium channel complex. Calcium channels mediate the influx of calcium ions into the cell upon membrane polarization and consist of a complex of alpha-1, alpha-2/delta, beta, and gamma subunits in a 1:1:1:1 ratio. The alpha-1 subunit has 24 transmembrane segments and forms the pore through which ions pass into the cell. There are multiple isoforms of each of the proteins in the complex, either encoded by different genes or the result of alternative splicing of transcripts. Alternate transcriptional splice variants, encoding different isoforms, have been characterized for the gene described here. Studies suggest certain mutations in this gene lead to childhood absence epilepsy (CAE). [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.84).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CACNA1H	NM_021098.3	c.2603+3G>A		splice_donor_region_variant, intron_variant		ENST00000348261.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CACNA1H	ENST00000348261.11	c.2603+3G>A		splice_donor_region_variant, intron_variant		1	NM_021098.3	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD3 exomes AF: 0.00000815 AC: 2 AN: 245410 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 133384

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000584

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000138 AC: 2 AN: 1449802 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 719060

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000450

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Idiopathic generalized epilepsy;C4310756:Hyperaldosteronism, familial, type IV Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jan 15, 2024

This sequence change falls in intron 11 of the CACNA1H gene. It does not directly change the encoded amino acid sequence of the CACNA1H protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs773966897, gnomAD 0.006%). This variant has not been reported in the literature in individuals affected with CACNA1H-related conditions. ClinVar contains an entry for this variant (Variation ID: 566036). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
Cadd	Benign	14
Dann	Benign	0.72

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000060
dbscSNV1_RF	Benign	0.098
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

Publications

LitVar

Other links and lift over

dbSNP: rs773966897; hg19: chr16-1255268;