NM_000070.3:c.668A>G

Variant names:

• chr15-42388963-A-G
• rs1160341980
• NM_000070.3:c.668A>G

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 6P and 1B. PM1 PM2 PM5 BP4

The NM_000070.3(CAPN3):​c.668A>G​(p.Asn223Ser) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,838 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. N223T) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CAPN3 NM_000070.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.23
• 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):

• 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: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 13 uncertain in NM_000070.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr15-42388963-A-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 3544376.Status of the report is no_assertion_criteria_provided, 0 stars.
• BP4: Computational evidence support a benign effect (MetaRNN=0.31710857).

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.668A>G	p.Asn223Ser	missense	Exon 5 of 24	NP_000061.1
	CAPN3	NM_024344.2		c.668A>G	p.Asn223Ser	missense	Exon 5 of 23	NP_077320.1
	CAPN3	NM_173087.2		c.668A>G	p.Asn223Ser	missense	Exon 5 of 21	NP_775110.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CAPN3	ENST00000397163.8	TSL:1 MANE Select	c.668A>G	p.Asn223Ser	missense	Exon 5 of 24	ENSP00000380349.3
	CAPN3	ENST00000357568.8	TSL:1	c.668A>G	p.Asn223Ser	missense	Exon 5 of 23	ENSP00000350181.3
	CAPN3	ENST00000349748.8	TSL:1	c.668A>G	p.Asn223Ser	missense	Exon 5 of 21	ENSP00000183936.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461838 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727220

⚠️ 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: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ 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

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Uncertain	0.099	D
BayesDel_noAF	Benign	-0.10
CADD	Uncertain	25
DANN	Uncertain	0.98
DEOGEN2	Benign	0.073	T
Eigen	Benign	-0.025
Eigen_PC	Benign	0.18
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.95	D
M_CAP	Uncertain	0.12	D
MetaRNN	Benign	0.32	T
MetaSVM	Uncertain	0.43	D
MutationAssessor	Benign	-0.34	N
PhyloP100		5.2
PrimateAI	Uncertain	0.75	T
PROVEAN	Benign	-0.39	N
REVEL	Uncertain	0.57
Sift	Benign	1.0	T
Sift4G	Benign	1.0	T
Polyphen		0.52	P
Vest4		0.18
MutPred		0.47		Gain of phosphorylation at N223 (P = 0.0677)
MVP		0.90
MPC		0.48
ClinPred		0.90	D
GERP RS		5.4
Varity_R		0.50
gMVP		0.67

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

Other links and lift over

dbSNP: rs1160341980; hg19: chr15-42681161;