NM_021098.3:c.6718G>C

Variant names:

• chr16-1220650-G-C
• rs774116060
• NM_021098.3:c.6718G>C

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_021098.3(CACNA1H):​c.6718G>C​(p.Ala2240Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,452,088 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign 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. A2240T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CACNA1H NM_021098.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -1.37
• Publications: 0 publications found

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]

CACNA1H Gene-Disease associations (from GenCC):

• hyperaldosteronism, familial, type IV

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• childhood absence epilepsy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• epilepsy, childhood absence, susceptibility to, 6

  Inheritance: AD Classification: LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.10431567).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_021098.3. 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
	CACNA1H	NM_021098.3	MANE Select	c.6718G>C	p.Ala2240Pro	missense	Exon 35 of 35	NP_066921.2
	CACNA1H	NM_001005407.2		c.6700G>C	p.Ala2234Pro	missense	Exon 34 of 34	NP_001005407.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNA1H	ENST00000348261.11	TSL:1 MANE Select	c.6718G>C	p.Ala2240Pro	missense	Exon 35 of 35	ENSP00000334198.7
	CACNA1H	ENST00000569107.6	TSL:1	c.6733G>C	p.Ala2245Pro	missense	Exon 34 of 34	ENSP00000454990.2
	CACNA1H	ENST00000711493.1		c.6703G>C	p.Ala2235Pro	missense	Exon 34 of 34	ENSP00000518778.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1452088 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 721728

⚠️ 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: 33146

American (AMR) AF: 0.00 AC: 0 AN: 43416

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25836

East Asian (EAS) AF: 0.00 AC: 0 AN: 39346

South Asian (SAS) AF: 0.00 AC: 0 AN: 85656

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51368

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5570

European-Non Finnish (NFE) AF: 9.03e-7 AC: 1 AN: 1107794

Other (OTH) AF: 0.00 AC: 0 AN: 59956

⚠️ 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	Benign	0.072
BayesDel_addAF	Benign	-0.25	T
BayesDel_noAF	Benign	-0.60
CADD	Benign	0.078
DANN	Benign	0.43
DEOGEN2	Benign	0.085	T
Eigen	Benign	-1.6
Eigen_PC	Benign	-1.7
FATHMM_MKL	Benign	0.032	N
LIST_S2	Benign	0.54	T
M_CAP	Pathogenic	0.74	D
MetaRNN	Benign	0.10	T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	1.1	L
PhyloP100		-1.4
PrimateAI	Uncertain	0.54	T
PROVEAN	Benign	0.14	N
REVEL	Benign	0.041
Sift	Benign	0.16	T
Sift4G	Benign	0.15	T
Polyphen		0.0020	B
Vest4		0.055
MutPred		0.11		Loss of catalytic residue at A2240 (P = 0.0357)
MVP		0.43
ClinPred		0.15	T
GERP RS		-3.6
Varity_R		0.085
gMVP		0.064
Mutation Taster		=95/5	polymorphism

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: rs774116060; hg19: chr16-1270650;