rs1555515661

Positions:

• chr16-1209267-A-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_021098.3(CACNA1H):​c.3599A>C​(p.Asp1200Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000714 in 1,400,314 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: 7.1e-7 (0 hom.)
• Consequence: CACNA1H NM_021098.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 3.27

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 Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.40273336).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CACNA1H	NM_021098.3	c.3599A>C	p.Asp1200Ala	missense_variant	17/35	ENST00000348261.11	NP_066921.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CACNA1H	ENST00000348261.11	c.3599A>C	p.Asp1200Ala	missense_variant	17/35	1	NM_021098.3	ENSP00000334198	P4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 7.14e-7 AC: 1 AN: 1400314 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 692546

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000276

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

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Epilepsy, childhood absence, susceptibility to, 6 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Baylor Genetics

Jun 04, 2018

This variant was determined to be of uncertain significance according to ACMG Guidelines, 2015 [PMID:25741868]. -

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Sep 03, 2017

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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with CACNA1H-related disease. While this variant is not present in population databases, the frequency information is unreliable, as metrics indicate poor data quality at this position in the ExAC database. This sequence change replaces aspartic acid with alanine at codon 1200 of the CACNA1H protein (p.Asp1200Ala). The aspartic acid residue is moderately conserved and there is a moderate physicochemical difference between aspartic acid and alanine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Uncertain	0.13	D
BayesDel_noAF	Uncertain	-0.040
CADD	Benign	19
DANN	Benign	0.90
DEOGEN2	Uncertain	0.52	D;.;.;.
Eigen	Benign	-0.39
Eigen_PC	Benign	-0.47
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Benign	0.76	T;T;T;.
M_CAP	Pathogenic	0.48	D
MetaRNN	Benign	0.40	T;T;T;T
MetaSVM	Uncertain	0.20	D
MutationAssessor	Uncertain	2.7	M;.;M;M
MutationTaster	Benign	1.0	N;N;N
PrimateAI	Uncertain	0.73	T
PROVEAN	Uncertain	-3.8	D;.;D;D
REVEL	Benign	0.28
Sift	Uncertain	0.011	D;.;D;D
Sift4G	Benign	0.075	T;.;T;T
Polyphen		0.0040	B;.;B;B
Vest4		0.38
MutPred		0.30		Gain of MoRF binding (P = 0.0326);.;Gain of MoRF binding (P = 0.0326);Gain of MoRF binding (P = 0.0326);
MVP		0.88
ClinPred		0.77	D
GERP RS		1.4
Varity_R		0.16
gMVP		0.64

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

Publications

LitVar

Other links and lift over

dbSNP: rs1555515661; hg19: chr16-1259267;