NM_001127222.2:c.4979G>C

Variant names:

• chr19-13235702-C-G
• rs121908216
• NM_001127222.2:c.4979G>C

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_001127222.2(CACNA1A):​c.4979G>C​(p.Arg1660Pro) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic 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. R1660C) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 31)
• Consequence: CACNA1A NM_001127222.2 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.10
• Publications: 0 publications found

Genes affected

CACNA1A (HGNC:1388): (calcium voltage-gated channel subunit alpha1 A) Voltage-dependent calcium channels mediate the entry of calcium ions into excitable cells, and are also involved in a variety of calcium-dependent processes, including muscle contraction, hormone or neurotransmitter release, and gene expression. Calcium channels are multisubunit complexes composed of alpha-1, beta, alpha-2/delta, and gamma subunits. The channel activity is directed by the pore-forming alpha-1 subunit, whereas, the others act as auxiliary subunits regulating this activity. The distinctive properties of the calcium channel types are related primarily to the expression of a variety of alpha-1 isoforms, alpha-1A, B, C, D, E, and S. This gene encodes the alpha-1A subunit, which is predominantly expressed in neuronal tissue. Mutations in this gene are associated with 2 neurologic disorders, familial hemiplegic migraine and episodic ataxia 2. This gene also exhibits polymorphic variation due to (CAG)n-repeats. Multiple transcript variants encoding different isoforms have been found for this gene. In one set of transcript variants, the (CAG)n-repeats occur in the 3' UTR, and are not associated with any disease. But in another set of variants, an insertion extends the coding region to include the (CAG)n-repeats which encode a polyglutamine tract. Expansion of the (CAG)n-repeats from the normal 4-18 to 21-33 in the coding region is associated with spinocerebellar ataxia 6. [provided by RefSeq, Jul 2016]

CACNA1A Gene-Disease associations (from GenCC):

• episodic ataxia type 2

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• undetermined early-onset epileptic encephalopathy

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, Illumina
• developmental and epileptic encephalopathy, 42

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• migraine, familial hemiplegic, 1

  Inheritance: AD Classification: STRONG Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• spinocerebellar ataxia type 6

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), Orphanet
• benign paroxysmal torticollis of infancy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial or sporadic hemiplegic migraine

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Lennox-Gastaut syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 4 uncertain in NM_001127222.2
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr19-13235703-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1308366.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.959

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CACNA1A	NM_001127222.2	c.4979G>C	p.Arg1660Pro	missense_variant	Exon 32 of 47	ENST00000360228.11	NP_001120694.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CACNA1A	ENST00000360228.11	c.4979G>C	p.Arg1660Pro	missense_variant	Exon 32 of 47	1	NM_001127222.2	ENSP00000353362.5
CACNA1A	ENST00000638029.1	c.4997G>C	p.Arg1666Pro	missense_variant	Exon 33 of 48	5		ENSP00000489829.1
CACNA1A	ENST00000573710.7	c.4985G>C	p.Arg1662Pro	missense_variant	Exon 32 of 47	5		ENSP00000460092.3
CACNA1A	ENST00000635727.1	c.4982G>C	p.Arg1661Pro	missense_variant	Exon 32 of 47	5		ENSP00000490001.1
CACNA1A	ENST00000637769.1	c.4982G>C	p.Arg1661Pro	missense_variant	Exon 32 of 47	1		ENSP00000489778.1
CACNA1A	ENST00000636012.1	c.4982G>C	p.Arg1661Pro	missense_variant	Exon 32 of 46	5		ENSP00000490223.1
CACNA1A	ENST00000637736.1	c.4841G>C	p.Arg1614Pro	missense_variant	Exon 31 of 46	5		ENSP00000489861.1
CACNA1A	ENST00000636389.1	c.4982G>C	p.Arg1661Pro	missense_variant	Exon 32 of 47	5		ENSP00000489992.1
CACNA1A	ENST00000637432.1	c.4997G>C	p.Arg1666Pro	missense_variant	Exon 33 of 48	5		ENSP00000490617.1
CACNA1A	ENST00000636549.1	c.4988G>C	p.Arg1663Pro	missense_variant	Exon 33 of 48	5		ENSP00000490578.1
CACNA1A	ENST00000637927.1	c.4985G>C	p.Arg1662Pro	missense_variant	Exon 32 of 47	5		ENSP00000489715.1
CACNA1A	ENST00000635895.1	c.4982G>C	p.Arg1661Pro	missense_variant	Exon 32 of 47	5		ENSP00000490323.1
CACNA1A	ENST00000638009.2	c.4982G>C	p.Arg1661Pro	missense_variant	Exon 32 of 47	1		ENSP00000489913.1
CACNA1A	ENST00000637276.1	c.4982G>C	p.Arg1661Pro	missense_variant	Exon 32 of 46	5		ENSP00000489777.1
CACNA1A	ENST00000636768.2	n.4982G>C		non_coding_transcript_exon_variant	Exon 32 of 45	5		ENSP00000490190.2
CACNA1A	ENST00000713789.1	n.*160G>C		non_coding_transcript_exon_variant	Exon 33 of 47			ENSP00000519091.1
CACNA1A	ENST00000713789.1	n.*160G>C		3_prime_UTR_variant	Exon 33 of 47			ENSP00000519091.1

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.55	D
BayesDel_noAF	Pathogenic	0.55
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.50	.;.;D;.;.;.;.;.;D;.;.;D;.;.;.;D;.;.;.;.
Eigen	Pathogenic	0.83
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.96	D;D;D;D;D;D;D;D;D;D;.;D;D;D;D;D;D;D;D;D
M_CAP	Pathogenic	0.85	D
MetaRNN	Pathogenic	0.96	D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.4	.;.;.;.;H;.;.;.;.;.;.;.;.;.;H;.;.;.;.;.
PhyloP100		4.1
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-6.6	.;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0010	.;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.;.
Sift4G	Pathogenic	0.0010	D;D;.;.;.;D;.;.;.;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.89
MutPred		0.81		.;.;Loss of MoRF binding (P = 0.0028);Loss of MoRF binding (P = 0.0028);Loss of MoRF binding (P = 0.0028);.;.;Loss of MoRF binding (P = 0.0028);.;.;.;Loss of MoRF binding (P = 0.0028);Loss of MoRF binding (P = 0.0028);.;Loss of MoRF binding (P = 0.0028);.;.;.;.;.;
MVP		0.97
MPC		1.7
ClinPred		1.0	D
GERP RS		5.0
Varity_R		0.95
gMVP		1.0
Mutation Taster		=3/97	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.13		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: rs121908216; hg19: chr19-13346516;