rs142004418

Positions:

• chr15-42402878-C-G
• chr15-42402878-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM5 PP3_Strong

The NM_000070.3(CAPN3):​c.1621C>G​(p.Arg541Gly) variant causes a missense change. The variant allele was found at a frequency of 0.00000958 in 1,461,788 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. R541P) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000096 (0 hom.)
• Consequence: CAPN3 NM_000070.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2 O:1
• Conservation: PhyloP100: 3.88

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a region_of_interest Domain III (size 168) in uniprot entity CAN3_HUMAN there are 132 pathogenic changes around while only 0 benign (100%) in NM_000070.3
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr15-42402879-G-C is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CAPN3	NM_000070.3	c.1621C>G	p.Arg541Gly	missense_variant	13/24	ENST00000397163.8	NP_000061.1
CAPN3	NM_024344.2	c.1621C>G	p.Arg541Gly	missense_variant	13/23		NP_077320.1
CAPN3	NM_173087.2	c.1477C>G	p.Arg493Gly	missense_variant	12/21		NP_775110.1
CAPN3	NM_173088.2	c.85C>G	p.Arg29Gly	missense_variant	2/13		NP_775111.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CAPN3	ENST00000397163.8	c.1621C>G	p.Arg541Gly	missense_variant	13/24	1	NM_000070.3	ENSP00000380349	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251424 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135884

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000958 AC: 14 AN: 1461788 Hom.: 0 Cov.: 33 AF XY: 0.0000110 AC XY: 8 AN XY: 727212

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000126

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 13, 2021

This sequence change replaces arginine with glycine at codon 541 of the CAPN3 protein (p.Arg541Gly). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and glycine. This variant is not present in population databases (ExAC no frequency). This missense change has been observed in individual(s) with clinical features of CAPN3-related conditions (Invitae). ClinVar contains an entry for this variant (Variation ID: 282677). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant disrupts the p.Arg541 amino acid residue in CAPN3. Other variant(s) that disrupt this residue have been observed in individuals with CAPN3-related conditions (PMID: 14981715, 16141003), which suggests that this may be a clinically significant amino acid residue. 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. -

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Eurofins Ntd Llc (ga)

Oct 06, 2015

- -

CAPN3-related disorder Other:1

not provided, no classification provided

phenotyping only

GenomeConnect - Invitae Patient Insights Network

-

Variant interpreted as Uncertain significance and reported on 03-09-2020 by Invitae. GenomeConnect-Invitae Patient Insights Network assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. Registry team members make no attempt to reinterpret the clinical significance of the variant. Phenotypic details are available under supporting information. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.84	D;.;.;D;.;.
Eigen	Pathogenic	0.86
Eigen_PC	Pathogenic	0.76
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Pathogenic	0.99	D;D;D;D;D;D
M_CAP	Pathogenic	0.52	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D
MetaSVM	Pathogenic	0.99	D
MutationAssessor	Pathogenic	3.9	.;H;.;H;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-6.2	D;D;D;D;D;D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0010	D;D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D;D
Polyphen		0.99, 1.0, 0.99	.;D;D;D;.;.
Vest4		0.98
MutPred		0.94		.;Loss of MoRF binding (P = 0.0248);.;Loss of MoRF binding (P = 0.0248);.;.;
MVP		0.97
MPC		0.70
ClinPred		0.99	D
GERP RS		4.9
Varity_R		0.96
gMVP		0.92

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: rs142004418; hg19: chr15-42695076;