NM_000726.5:c.1417C>T

Variant names:

• chr2-151839265-G-A
• rs755031838
• NM_000726.5:c.1417C>T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BS2

The NM_000726.5(CACNB4):​c.1417C>T​(p.Arg473Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000496 in 1,613,482 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R473H) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: CACNB4 NM_000726.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 7.49
• Publications: 1 publications found

Genes affected

CACNB4 (HGNC:1404): (calcium voltage-gated channel auxiliary subunit beta 4) This gene encodes a member of the beta subunit family of voltage-dependent calcium channel complex proteins. 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. Various versions of each of these subunits exist, either expressed from similar genes or the result of alternative splicing. The protein encoded by this locus plays an important role in calcium channel function by modulating G protein inhibition, increasing peak calcium current, controlling the alpha-1 subunit membrane targeting and shifting the voltage dependence of activation and inactivation. Certain mutations in this gene have been associated with idiopathic generalized epilepsy (IGE), juvenile myoclonic epilepsy (JME), and episodic ataxia, type 5. [provided by RefSeq, Aug 2016]

CACNB4 Gene-Disease associations (from GenCC):

• episodic ataxia type 5

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• juvenile myoclonic epilepsy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• epilepsy, idiopathic generalized, susceptibility to, 9

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

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ENSG00000283228 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BS2: High AC in GnomAdExome4 at 7 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CACNB4	NM_000726.5	c.1417C>T	p.Arg473Cys	missense_variant	Exon 14 of 14	ENST00000539935.7	NP_000717.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CACNB4	ENST00000539935.7	c.1417C>T	p.Arg473Cys	missense_variant	Exon 14 of 14	1	NM_000726.5	ENSP00000438949.1
ENSG00000283228	ENST00000637559.1	n.*332+2638C>T		intron_variant	Intron 10 of 11	5		ENSP00000489697.1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152056 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.00000803 AC: 2 AN: 249054 AF XY: 0.00000740

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

Gnomad ASJ exome AF: 0.00

Gnomad EAS 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: 0.00000479 AC: 7 AN: 1461426 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727002

African (AFR) AF: 0.0000598 AC: 2 AN: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.0000348 AC: 3 AN: 86242

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53400

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111636

Other (OTH) AF: 0.0000166 AC: 1 AN: 60368

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152056 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74292

African (AFR) AF: 0.00 AC: 0 AN: 41392

American (AMR) AF: 0.00 AC: 0 AN: 15272

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10594

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 67998

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ExAC AF: 0.00000827 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Apr 26, 2017

Athena Diagnostics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Idiopathic generalized epilepsy Uncertain:1

Jun 09, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 446968). This variant has not been reported in the literature in individuals affected with CACNB4-related conditions. This variant is present in population databases (rs755031838, gnomAD 0.003%). This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 473 of the CACNB4 protein (p.Arg473Cys). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.35
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	0.070
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.31	T;.;.;T;T;T;T;T;.;T;.;T;T;.;.;.;T;T;.;.;.;T;.;T;T;T;.;.
Eigen	Pathogenic	0.74
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D;D;D;.;.;D;.;D;D;D;D;D;D;D;D;.;D;D;D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.16	D
MetaRNN	Uncertain	0.59	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.13	D
MutationAssessor	Benign	1.7	L;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.
PhyloP100		7.5
PrimateAI	Pathogenic	0.81	D
PROVEAN	Benign	-1.5	N;.;.;.;.;.;.;.;.;.;.;.;.;.;N;.;.;.;.;.;.;.;.;.;.;.;.;N
REVEL	Uncertain	0.44
Sift	Benign	0.030	D;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.;.;D
Sift4G	Uncertain	0.011	D;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.;.;D
Polyphen		1.0	D;.;.;.;.;.;.;.;.;.;.;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.57
MutPred		0.29		Gain of catalytic residue at L474 (P = 0.0312);.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;
MVP		0.87
MPC		1.8
ClinPred		0.91	D
GERP RS		5.3
Varity_R		0.25
gMVP		0.56
Mutation Taster		=53/47	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: rs755031838; hg19: chr2-152695779;