rs769688710

Variant names:

• chr15-42411745-A-G
• rs769688710
• NM_000070.3:c.2440-2A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PVS1_Strong PM2 PP5

The NM_000070.3(CAPN3):​c.2440-2A>G variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). The gene CAPN3 is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 26)
  • Exomes 𝑓: 0.0000015 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CAPN3 NM_000070.3 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1
• Conservation: PhyloP100: 8.61
• Publications: 0 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):

• muscular dystrophy, limb-girdle, autosomal dominant

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• 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: Myriad Women’s Health, Orphanet, Labcorp Genetics (formerly Invitae)
• limb-girdle muscular dystrophy

  Inheritance: SD Classification: DEFINITIVE Submitted by: ClinGen
• muscular dystrophy, limb-girdle, autosomal dominant 4

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

ENSG00000258461 (HGNC:):

ACMG classification

Specifications for CAPN3 are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Likely_pathogenic. The variant received 7 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.23154907 fraction of the gene. Cryptic splice site detected, with MaxEntScore 7, offset of 9, new splice context is: acttctttcggtggctgcAGctc. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 15-42411745-A-G is Pathogenic according to our data. Variant chr15-42411745-A-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 446979.

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CAPN3	NM_000070.3	MANE Select	c.2440-2A>G		splice_acceptor intron	N/A	NP_000061.1	P20807-1
	CAPN3	NM_024344.2		c.2422-2A>G		splice_acceptor intron	N/A	NP_077320.1	P20807-3
	CAPN3	NM_173087.2		c.2164-2A>G		splice_acceptor intron	N/A	NP_775110.1	P20807-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CAPN3	ENST00000397163.8	TSL:1 MANE Select	c.2440-2A>G		splice_acceptor intron	N/A	ENSP00000380349.3	P20807-1
	CAPN3	ENST00000357568.8	TSL:1	c.2422-2A>G		splice_acceptor intron	N/A	ENSP00000350181.3	P20807-3
	CAPN3	ENST00000349748.8	TSL:1	c.2164-2A>G		splice_acceptor intron	N/A	ENSP00000183936.4	P20807-2

Frequencies

GnomAD3 genomes Cov.: 26

GnomAD2 exomes AF: 0.00000400 AC: 1 AN: 249924 AF XY: 0.00

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 FIN exome AF: 0.0000462

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.00000148 AC: 2 AN: 1352316 Hom.: 0 Cov.: 27 AF XY: 0.00000295 AC XY: 2 AN XY: 677752

⚠️ 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: 31770

American (AMR) AF: 0.00 AC: 0 AN: 44360

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25284

East Asian (EAS) AF: 0.00 AC: 0 AN: 38586

South Asian (SAS) AF: 0.00 AC: 0 AN: 84270

European-Finnish (FIN) AF: 0.0000190 AC: 1 AN: 52634

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5416

European-Non Finnish (NFE) AF: 9.87e-7 AC: 1 AN: 1013438

Other (OTH) AF: 0.00 AC: 0 AN: 56558

⚠️ 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.: 26

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
1	-	-	Autosomal recessive limb-girdle muscular dystrophy type 2A (1)
-	1	-	Autosomal recessive limb-girdle muscular dystrophy type 2A;C4748295:Muscular dystrophy, limb-girdle, autosomal dominant 4 (1)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.40
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		8.6
GERP RS		6.0
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.92
SpliceAI score (max)		0.89		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.58		Position offset: 11
DS_AL_spliceai		0.89		Position offset: 2

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

Other links and lift over

dbSNP: rs769688710; hg19: chr15-42703943;