2-151839182-G-T

Variant names:

• chr2-151839182-G-T
• rs749277227
• NM_000726.5:c.1500C>A

Variant summary

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

The NM_000726.5(CACNB4):​c.1500C>A​(p.Tyr500*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,270 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. Y500Y) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: CACNB4 NM_000726.5 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.30
• Publications: 0 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: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000726.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNB4	NM_000726.5	MANE Select	c.1500C>A	p.Tyr500*	stop_gained	Exon 14 of 14	NP_000717.2
	CACNB4	NM_001005746.4		c.1446C>A	p.Tyr482*	stop_gained	Exon 14 of 14	NP_001005746.1
	CACNB4	NM_001005747.4		c.1398C>A	p.Tyr466*	stop_gained	Exon 13 of 13	NP_001005747.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNB4	ENST00000539935.7	TSL:1 MANE Select	c.1500C>A	p.Tyr500*	stop_gained	Exon 14 of 14	ENSP00000438949.1
	CACNB4	ENST00000534999.7	TSL:1	c.1398C>A	p.Tyr466*	stop_gained	Exon 13 of 13	ENSP00000443893.1
	CACNB4	ENST00000201943.10	TSL:1	c.1314C>A	p.Tyr438*	stop_gained	Exon 13 of 13	ENSP00000201943.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461270 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 726924

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86242

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53398

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111498

Other (OTH) AF: 0.00 AC: 0 AN: 60360

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Pathogenic	0.60
CADD	Pathogenic	36
DANN	Uncertain	1.0
Eigen	Uncertain	0.58
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		3.3
Vest4		0.72
GERP RS		2.1
Mutation Taster		=17/183	disease causing

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: rs749277227; hg19: chr2-152695696;