rs587780291

chr15-42384544-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000070.3(CAPN3):c.371G>C(p.Gly124Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,460,802 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 Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. G124G) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: CAPN3 NM_000070.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:5
• Conservation: PhyloP100: 10.0

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]

LOC105370794 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000070.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CAPN3	NM_000070.3	c.371G>C	p.Gly124Ala	missense_variant	2/24	ENST00000397163.8
CAPN3	NM_024344.2	c.371G>C	p.Gly124Ala	missense_variant	2/23
CAPN3	NM_173087.2	c.371G>C	p.Gly124Ala	missense_variant	2/21
LOC105370794	XR_932178.3			downstream_gene_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CAPN3	ENST00000397163.8	c.371G>C	p.Gly124Ala	missense_variant	2/24	1	NM_000070.3	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251394 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 135856

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

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 AF: 0.00000274 AC: 4 AN: 1460802 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 726766

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000671

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: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000756

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:5

Revision: criteria provided, conflicting classifications

Submissions by phenotype

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

Uncertain significance, no assertion criteria provided	clinical testing	Natera, Inc.	Sep 16, 2020	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Dec 27, 2023	This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 124 of the CAPN3 protein (p.Gly124Ala). This variant is present in population databases (rs587780291, gnomAD 0.006%). 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: 128571). 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 expected to disrupt CAPN3 protein function with a positive predictive value of 80%. 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. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Genetic Services Laboratory, University of Chicago	Nov 07, 2013	- -

not provided Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Athena Diagnostics	May 23, 2022	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Sep 29, 2017	- -

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 10, 2022

The c.371G>C (p.G124A) alteration is located in exon 2 (coding exon 2) of the CAPN3 gene. This alteration results from a G to C substitution at nucleotide position 371, causing the glycine (G) at amino acid position 124 to be replaced by an alanine (A). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.53
Cadd	Pathogenic	31
Dann	Uncertain	1.0
DEOGEN2	Uncertain	0.70	D;.;.;D
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	D;D;D;D
M_CAP	Pathogenic	0.57	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.79	T
PROVEAN	Pathogenic	-5.6	D;D;D;D
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0, 1.0, 1.0	.;D;D;D
Vest4		0.96
MutPred		0.96		Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);Gain of sheet (P = 0.1945);
MVP		0.99
MPC		0.65
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.97
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: rs587780291; hg19: chr15-42676742;