7-45000353-AG-A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_031443.4(CCM2):c.23del(p.Gly8AlafsTer15) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 25)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CCM2 NM_031443.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 3.88

Genes affected

CCM2 (HGNC:21708): (CCM2 scaffold protein) This gene encodes a scaffold protein that functions in the stress-activated p38 Mitogen-activated protein kinase (MAPK) signaling cascade. The protein interacts with SMAD specific E3 ubiquitin protein ligase 1 (also known as SMURF1) via a phosphotyrosine binding domain to promote RhoA degradation. The protein is required for normal cytoskeletal structure, cell-cell interactions, and lumen formation in endothelial cells. Mutations in this gene result in cerebral cavernous malformations. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Nov 2009]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 44 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-45000353-AG-A is Pathogenic according to our data. Variant chr7-45000353-AG-A is described in ClinVar as [Pathogenic]. Clinvar id is 2680.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CCM2	NM_031443.4	c.23del	p.Gly8AlafsTer15	frameshift_variant	1/10	ENST00000258781.11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CCM2	ENST00000258781.11	c.23del	p.Gly8AlafsTer15	frameshift_variant	1/10	1	NM_031443.4	P1

Frequencies

GnomAD3 genomes Cov.: 25

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1139468 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 550080

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 25

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Cerebral cavernous malformation 2 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Aug 22, 2023	For these reasons, this variant has been classified as Pathogenic. This sequence change creates a premature translational stop signal (p.Gly8Alafs*15) in the CCM2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CCM2 are known to be pathogenic (PMID: 18300272, 24689081). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with cerebral cavernous malformations (PMID: 14624391). It has also been observed to segregate with disease in related individuals. This variant is also known as 8fsX22. ClinVar contains an entry for this variant (Variation ID: 2680). -
Pathogenic, no assertion criteria provided	literature only	OMIM	Dec 01, 2003	- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs1562848466; hg19: chr7-45039952;