3-8745551-A-G

Variant names:

• chr3-8745551-A-G
• rs199476327
• NM_033337.3:c.140A>G

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_033337.3(CAV3):​c.140A>G​(p.Glu47Gly) variant causes a missense 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. 13/22 in silico tools predict a damaging 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. E47D) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CAV3 NM_033337.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.87
• Publications: 0 publications found

Genes affected

CAV3 (HGNC:1529): (caveolin 3) This gene encodes a caveolin family member, which functions as a component of the caveolae plasma membranes found in most cell types. Caveolin proteins are proposed to be scaffolding proteins for organizing and concentrating certain caveolin-interacting molecules. Mutations identified in this gene lead to interference with protein oligomerization or intra-cellular routing, disrupting caveolae formation and resulting in Limb-Girdle muscular dystrophy type-1C (LGMD-1C), hyperCKemia or rippling muscle disease (RMD). Alternative splicing has been identified for this locus, with inclusion or exclusion of a differentially spliced intron. In addition, transcripts utilize multiple polyA sites and contain two potential translation initiation sites. [provided by RefSeq, Jul 2008]

OXTR (HGNC:8529): (oxytocin receptor) The protein encoded by this gene belongs to the G-protein coupled receptor family and acts as a receptor for oxytocin. Its activity is mediated by G proteins which activate a phosphatidylinositol-calcium second messenger system. The oxytocin-oxytocin receptor system plays an important role in the uterus during parturition. [provided by RefSeq, Jul 2008]

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 24 uncertain in NM_033337.3
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 17 curated pathogenic missense variants (we use a threshold of 10). The gene has 2 curated benign missense variants. Gene score misZ: 0.83011 (below the threshold of 3.09). Trascript score misZ: 0.9876 (below the threshold of 3.09). GenCC associations: The gene is linked to rippling muscle disease 2, hypertrophic cardiomyopathy 1, long QT syndrome 9, distal myopathy, Tateyama type, inherited rippling muscle disease, Brugada syndrome, autosomal dominant limb-girdle muscular dystrophy type 1C, caveolinopathy, long QT syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.996

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CAV3	NM_033337.3	c.140A>G	p.Glu47Gly	missense_variant	Exon 2 of 2	ENST00000343849.3	NP_203123.1
CAV3	NM_001234.5	c.140A>G	p.Glu47Gly	missense_variant	Exon 2 of 3		NP_001225.1
OXTR	XR_007095681.1	n.1885-2949T>C		intron_variant	Intron 4 of 4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CAV3	ENST00000343849.3	c.140A>G	p.Glu47Gly	missense_variant	Exon 2 of 2	1	NM_033337.3	ENSP00000341940.2
CAV3	ENST00000397368.2	c.140A>G	p.Glu47Gly	missense_variant	Exon 2 of 3	1		ENSP00000380525.2
CAV3	ENST00000472766.1	n.155+11561A>G		intron_variant	Intron 1 of 2	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Long QT syndrome Uncertain:1

Apr 10, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 47 of the CAV3 protein (p.Glu47Gly). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with CAV3-related conditions. ClinVar contains an entry for this variant (Variation ID: 2011121). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. This variant disrupts the p.Glu47 amino acid residue in CAV3. Other variant(s) that disrupt this residue have been observed in individuals with CAV3-related conditions (PMID: 17405141, 18583131, 30174172), 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.59	D
BayesDel_noAF	Pathogenic	0.61
CADD	Pathogenic	26
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.98	D;D
Eigen	Pathogenic	0.73
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	.;D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	1.0	D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.7	H;H
PhyloP100		8.9
PrimateAI	Uncertain	0.71	T
PROVEAN	Pathogenic	-7.0	D;D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.92
MutPred		0.95		Loss of stability (P = 0.0157);Loss of stability (P = 0.0157);
MVP		1.0
MPC		1.6
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.93
gMVP		0.99
Mutation Taster		=16/84	disease causing

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: rs199476327; hg19: chr3-8787237;