NM_000070.3:c.1524+1G>A

Variant names:

• chr15-42401811-G-A
• rs1275289254
• NM_000070.3:c.1524+1G>A

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_000070.3(CAPN3):​c.1524+1G>A variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CAPN3 NM_000070.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 9.92
• Publications: 2 publications found

Genes affected

CAPN3 (HGNC:1480): (calpain 3) Calpain, a heterodimer consisting of a large and a small subunit, is a major intracellular protease, although its function has not been well established. This gene encodes a muscle-specific member of the calpain large subunit family that specifically binds to titin. Mutations in this gene are associated with limb-girdle muscular dystrophies type 2A. Alternate promoters and alternative splicing result in multiple transcript variants encoding different isoforms and some variants are ubiquitously expressed. [provided by RefSeq, Jul 2008]

CAPN3 Gene-Disease associations (from GenCC):

• autosomal recessive limb-girdle muscular dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• autosomal recessive limb-girdle muscular dystrophy type 2A

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, Myriad Women’s Health, Labcorp Genetics (formerly Invitae)
• muscular dystrophy, limb-girdle, autosomal dominant 4

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• muscular dystrophy, limb-girdle, autosomal dominant

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ENSG00000258461 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 15-42401811-G-A is Pathogenic according to our data. Variant chr15-42401811-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 536512.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000070.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CAPN3	NM_000070.3	MANE Select	c.1524+1G>A		splice_donor intron	N/A	NP_000061.1
	CAPN3	NM_024344.2		c.1524+1G>A		splice_donor intron	N/A	NP_077320.1
	CAPN3	NM_173087.2		c.1380+1G>A		splice_donor intron	N/A	NP_775110.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CAPN3	ENST00000397163.8	TSL:1 MANE Select	c.1524+1G>A		splice_donor intron	N/A	ENSP00000380349.3
	CAPN3	ENST00000357568.8	TSL:1	c.1524+1G>A		splice_donor intron	N/A	ENSP00000350181.3
	CAPN3	ENST00000349748.8	TSL:1	c.1380+1G>A		splice_donor intron	N/A	ENSP00000183936.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Muscular dystrophy, limb-girdle, autosomal dominant 4 Pathogenic:1

Mar 07, 2022

Baylor Genetics

Significance: Likely pathogenic

Review Status: flagged submission

Collection Method: clinical testing

Autosomal recessive limb-girdle muscular dystrophy type 2A Pathogenic:1

Feb 21, 2020

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. Donor and acceptor splice site variants typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in CAPN3 are known to be pathogenic (PMID: 10330340, 15689361). Experimental studies have shown that alteration of this splice site disrupts mRNA splicing (PMID: 20635405). Disruption of this splice site has been observed in individual(s) with autosomal recessive limb-girdle muscular dystrophy and Emery-Dreifuss muscular dystrophy (PMID: 17258832, 19556129, 20635405). ClinVar contains an entry for this variant (Variation ID: 536512). This variant is not present in population databases (ExAC no frequency). This sequence change affects a donor splice site in intron 11 of the CAPN3 gene. It is expected to disrupt RNA splicing and likely results in an absent or disrupted protein product.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.23
CADD	Pathogenic	32
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Uncertain	0.20	D
PhyloP100		9.9
ClinPred		0.97	D
GERP RS		4.9
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_DL_spliceai		1.0		Position offset: -1

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

Other links and lift over

dbSNP: rs1275289254; hg19: chr15-42694009;