4-15475965-TAC-T

Variant names:

• chr4-15475965-TAC-T
• rs764788925
• NM_001378615.1:c.35_36delCA

Variant summary

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

The NM_001378615.1(CC2D2A):​c.35_36delCA​(p.Thr12ArgfsTer5) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000209 in 1,437,944 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: CC2D2A NM_001378615.1 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 3.03

Genes affected

CC2D2A (HGNC:29253): (coiled-coil and C2 domain containing 2A) This gene encodes a coiled-coil and calcium binding domain protein that appears to play a critical role in cilia formation. Mutations in this gene cause Meckel syndrome type 6, as well as Joubert syndrome type 9. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Sep 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 81 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 4-15475965-TAC-T is Pathogenic according to our data. Variant chr4-15475965-TAC-T is described in ClinVar as [Pathogenic]. Clinvar id is 2926082.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CC2D2A	NM_001378615.1	c.35_36delCA	p.Thr12ArgfsTer5	frameshift_variant	Exon 2 of 37	ENST00000424120.6	NP_001365544.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CC2D2A	ENST00000424120.6	c.35_36delCA	p.Thr12ArgfsTer5	frameshift_variant	Exon 2 of 37	5	NM_001378615.1	ENSP00000403465.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000471 AC: 1 AN: 212430 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 113718

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: 0.0000385

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000209 AC: 3 AN: 1437944 Hom.: 0 AF XY: 0.00000281 AC XY: 2 AN XY: 712608

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: 0.0000365

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Meckel-Gruber syndrome;C0431399:Familial aplasia of the vermis Pathogenic:1

Dec 18, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant has not been reported in the literature in individuals affected with CC2D2A-related conditions. This variant is present in population databases (rs764788925, gnomAD 0.004%). This sequence change creates a premature translational stop signal (p.Thr12Argfs*5) in the CC2D2A gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CC2D2A are known to be pathogenic (PMID: 19777577). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs764788925; hg19: chr4-15477589;