chr1-201066878-G-T

Variant names:

• chr1-201066878-G-T
• rs375784883
• NM_000069.3:c.2657+9C>A

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_000069.3(CACNA1S):​c.2657+9C>A variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000688 in 1,453,246 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CACNA1S NM_000069.3 intron
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.59
• Publications: 0 publications found

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]

CACNA1S Gene-Disease associations (from GenCC):

• congenital myopathy 18

  Inheritance: AD, AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• hypokalemic periodic paralysis, type 1

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
• malignant hyperthermia, susceptibility to, 5

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Ambry Genetics
• congenital myopathy

  Inheritance: SD, AR, AD Classification: STRONG Submitted by: Illumina, Genomics England PanelApp
• hypokalemic periodic paralysis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000069.3. 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
	CACNA1S	NM_000069.3	MANE Select	c.2657+9C>A		intron	N/A	NP_000060.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CACNA1S	ENST00000362061.4	TSL:1 MANE Select	c.2657+9C>A		intron	N/A	ENSP00000355192.3
	CACNA1S	ENST00000367338.7	TSL:5	c.2657+9C>A		intron	N/A	ENSP00000356307.3
	CACNA1S	ENST00000681874.1		c.2597+9C>A		intron	N/A	ENSP00000505162.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.88e-7 AC: 1 AN: 1453246 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 723502

⚠️ 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: 33322

American (AMR) AF: 0.00 AC: 0 AN: 44702

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26082

East Asian (EAS) AF: 0.00 AC: 0 AN: 39648

South Asian (SAS) AF: 0.00 AC: 0 AN: 85988

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53374

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5732

European-Non Finnish (NFE) AF: 9.06e-7 AC: 1 AN: 1104248

Other (OTH) AF: 0.00 AC: 0 AN: 60150

⚠️ 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.: 32

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Malignant hyperthermia, susceptibility to, 5;C3714580:Hypokalemic periodic paralysis, type 1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.92
CADD	Benign	17
DANN	Benign	0.54
PhyloP100		-1.6

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.75		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.75		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs375784883; hg19: chr1-201036006;