1-201043414-C-T

Variant names:

• chr1-201043414-C-T
• rs758332515
• NM_000069.3:c.4915G>A

Variant summary

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

The NM_000069.3(CACNA1S):​c.4915G>A​(p.Glu1639Lys) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 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. E1639V) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CACNA1S NM_000069.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:8
• Conservation: PhyloP100: 6.25

Genes affected

CACNA1S (HGNC:1397): (calcium voltage-gated channel subunit alpha1 S) This gene encodes one of the five subunits of the slowly inactivating L-type voltage-dependent calcium channel in skeletal muscle cells. Mutations in this gene have been associated with hypokalemic periodic paralysis, thyrotoxic periodic paralysis and malignant hyperthermia susceptibility. [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=0.2853014).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CACNA1S	NM_000069.3	c.4915G>A	p.Glu1639Lys	missense_variant	Exon 40 of 44	ENST00000362061.4	NP_000060.2
CACNA1S	XM_005245478.4	c.4858G>A	p.Glu1620Lys	missense_variant	Exon 39 of 43		XP_005245535.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CACNA1S	ENST00000362061.4	c.4915G>A	p.Glu1639Lys	missense_variant	Exon 40 of 44	1	NM_000069.3	ENSP00000355192.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251478 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135920

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Malignant hyperthermia, susceptibility to, 5 Uncertain:2

Jun 26, 2023

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces glutamic acid with lysine at codon 1639 of the CACNA1S protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with CACNA1S-related disorders in the literature. This variant has been identified in 1/251478 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Apr 11, 2023

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified Uncertain:1

Jul 21, 2017

Athena Diagnostics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Hypokalemic periodic paralysis, type 1 Uncertain:1

Apr 11, 2023

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Congenital myopathy 18 Uncertain:1

Apr 11, 2023

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Thyrotoxic periodic paralysis, susceptibility to, 1 Uncertain:1

Apr 11, 2023

Genome-Nilou Lab

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Uncertain:1

Aug 22, 2023

Mayo Clinic Laboratories, Mayo Clinic

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Malignant hyperthermia, susceptibility to, 5;C3714580:Hypokalemic periodic paralysis, type 1 Uncertain:1

Nov 10, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 1639 of the CACNA1S protein (p.Glu1639Lys). This variant is present in population databases (rs758332515, gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CACNA1S-related conditions. ClinVar contains an entry for this variant (Variation ID: 446964). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt CACNA1S protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.27
BayesDel_addAF	Pathogenic	0.19	D
BayesDel_noAF	Uncertain	0.030
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.058	T;T
Eigen	Uncertain	0.32
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.95	D;D
M_CAP	Uncertain	0.20	D
MetaRNN	Benign	0.29	T;T
MetaSVM	Uncertain	0.0022	D
MutationAssessor	Uncertain	2.4	.;M
PrimateAI	Uncertain	0.57	T
PROVEAN	Uncertain	-2.9	D;D
REVEL	Uncertain	0.44
Sift	Uncertain	0.012	D;D
Sift4G	Benign	0.31	T;T
Polyphen		0.61	.;P
Vest4		0.27
MutPred		0.29		.;Gain of ubiquitination at E1639 (P = 0.0029);
MVP		0.94
MPC		0.21
ClinPred		0.97	D
GERP RS		5.2
Varity_R		0.40
gMVP		0.57

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: rs758332515; hg19: chr1-201012542;