rs370880399

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_001378615.1(CC2D2A):​c.3055C>T​(p.Arg1019*) variant causes a stop gained change. The variant allele was found at a frequency of 0.0000591 in 1,606,748 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000092 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000056 ( 0 hom. )

Consequence

CC2D2A
NM_001378615.1 stop_gained

Scores

4
2
1

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:11

Conservation

PhyloP100: 4.82
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 4-15563395-C-T is Pathogenic according to our data. Variant chr4-15563395-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 217602.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr4-15563395-C-T is described in Lovd as [Pathogenic]. Variant chr4-15563395-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CC2D2ANM_001378615.1 linkc.3055C>T p.Arg1019* stop_gained Exon 24 of 37 ENST00000424120.6 NP_001365544.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CC2D2AENST00000424120.6 linkc.3055C>T p.Arg1019* stop_gained Exon 24 of 37 5 NM_001378615.1 ENSP00000403465.1 Q9P2K1-4

Frequencies

GnomAD3 genomes
AF:
0.0000920
AC:
14
AN:
152154
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.000480
GnomAD3 exomes
AF:
0.000102
AC:
24
AN:
236182
Hom.:
0
AF XY:
0.0000940
AC XY:
12
AN XY:
127678
show subpopulations
Gnomad AFR exome
AF:
0.0000696
Gnomad AMR exome
AF:
0.0000605
Gnomad ASJ exome
AF:
0.00133
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.0000346
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000470
Gnomad OTH exome
AF:
0.000343
GnomAD4 exome
AF:
0.0000557
AC:
81
AN:
1454594
Hom.:
0
Cov.:
31
AF XY:
0.0000650
AC XY:
47
AN XY:
722708
show subpopulations
Gnomad4 AFR exome
AF:
0.0000899
Gnomad4 AMR exome
AF:
0.0000920
Gnomad4 ASJ exome
AF:
0.00154
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000236
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000144
Gnomad4 OTH exome
AF:
0.000249
GnomAD4 genome
AF:
0.0000920
AC:
14
AN:
152154
Hom.:
0
Cov.:
33
AF XY:
0.0000807
AC XY:
6
AN XY:
74322
show subpopulations
Gnomad4 AFR
AF:
0.0000724
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00288
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.000480
Alfa
AF:
0.000195
Hom.:
0
Bravo
AF:
0.0000945
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ESP6500AA
AF:
0.000260
AC:
1
ESP6500EA
AF:
0.000241
AC:
2
ExAC
AF:
0.0000993
AC:
12

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:11
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Joubert syndrome 9 Pathogenic:3
Feb 23, 2015
UW Hindbrain Malformation Research Program, University of Washington
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

- -

Apr 27, 2023
Neurometabolic Diseases Laboratory, Bellvitge Biomedical Research Institute (IDIBELL)
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

- -

May 28, 2021
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

not provided Pathogenic:2
-
Department of Pathology and Laboratory Medicine, Sinai Health System
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

The CC2D2A p.R1019* variant was identified in the heterozygous or compound heterozygous state in 4 of 194 families with Joubert syndrome and related disorders (Gorden_2008_PMID:18950740; Bachmann-Gagescu_2012_PMID:22241855). The variant was identified in dbSNP (ID: rs370880399) and ClinVar (classified as pathogenic by Invitae, GeneDx, Fulgent Genetics, UW Hindbrain Malformation Research Program, University of Washington and as likely pathogenic by Illumina). The variant was identified in control databases in 26 of 267576 chromosomes at a frequency of 0.00009717 (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: Ashkenazi Jewish in 14 of 10098 chromosomes (freq: 0.001386), Other in 2 of 6912 chromosomes (freq: 0.000289), African in 2 of 23072 chromosomes (freq: 0.000087), Latino in 2 of 33894 chromosomes (freq: 0.000059), European (non-Finnish) in 5 of 121798 chromosomes (freq: 0.000041) and South Asian in 1 of 28914 chromosomes (freq: 0.000035), but was not observed in the East Asian or European (Finnish) populations. The c.3055C>T variant leads to a premature stop codon at position 1019 which is predicted to lead to a truncated or absent protein and loss of function. Loss of function variants of the CC2D2A gene are an established mechanism of disease in Joubert syndrome and related disorders and is the type of variant expected to cause the disorder when found in the homozygous or compound heterozygous state. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information this variant meets our laboratory’s criteria to be classified as pathogenic. -

Mar 13, 2025
GeneDx
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 25525159, 27081510, 19466712, 22241855, 26092869, 31589614, 33486889, 18950740, 29165578, 31964843) -

CC2D2A-related disorder Pathogenic:2
Nov 30, 2018
Illumina Laboratory Services, Illumina
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The CC2D2A c.3055C>T (p.Arg1019Ter) variant is a stop-gained variant that is predicted to cause premature truncation of the protein. This variant has been identified in at least four probands with Joubert syndrome, including in three in a compound heterozygous state with a missense variant and in one in a heterozygous state where a second variant was not detected (Gorden et al. 2008; Bachmann-Gagescu et al. 2012; Bachmann-Gagescu et al. 2015). The p.Arg1019Ter variant has also been reported in a homozygous state as a result of a different nucleotide substitution in one individual with Joubert syndrome (Ben-Salem et al. 2014). Control data are unavailable for this variant which is reported at a frequency of 0.00025 in the total population of the Exome Sequencing Project. Based on the evidence and due to the potential impact of stop-gained variants, the p.Arg1019Ter variant is classified as likely pathogenic for CC2D2A-related disorders. This variant was observed by ICSL as part of a predisposition screen in an ostensibly healthy population. -

Sep 14, 2023
PreventionGenetics, part of Exact Sciences
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The CC2D2A c.3055C>T variant is predicted to result in premature protein termination (p.Arg1019*). This variant has been reported in multiple individuals with Joubert syndrome (Gorden et al. 2008. PubMed ID: 18950740; Bachmann-Gagescu et al. 2015. PubMed ID: 26092869). We have also detected this variant in the compound heterozygous state in a child with Joubert syndrome (internal data, PreventionGenetics). Taken together, we interpret this variant as pathogenic. -

Meckel-Gruber syndrome;C0431399:Familial aplasia of the vermis Pathogenic:1
Dec 27, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg1019*) 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). This variant is present in population databases (rs370880399, gnomAD 0.2%). This premature translational stop signal has been observed in individual(s) with Joubert syndrome (PMID: 18950740, 22241855, 26092869, 27082236). ClinVar contains an entry for this variant (Variation ID: 217602). For these reasons, this variant has been classified as Pathogenic. -

Joubert syndrome 9;C2676790:Meckel syndrome, type 6;C5436837:COACH syndrome 2;C5676970:Retinitis pigmentosa 93 Pathogenic:1
Mar 20, 2024
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Joubert syndrome 9;C2676790:Meckel syndrome, type 6;C5435651:COACH syndrome 1 Pathogenic:1
Oct 31, 2018
Fulgent Genetics, Fulgent Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Meckel syndrome, type 6 Pathogenic:1
Jul 20, 2024
Cytogenetics and Genomics Lab, Cyprus Institute Of Neurology and Genetics
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: research

This is a null variant in a gene where loss-of-function is a known mechnism of disease (PVS1_very strong). It is found in extremely low frequency in gnomAD population database (PM2_supporting). Found in monochorionic diamniotic twins. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.62
CADD
Pathogenic
40
DANN
Uncertain
1.0
Eigen
Pathogenic
0.85
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Uncertain
0.96
D
Vest4
0.93
GERP RS
4.4

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.16
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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs370880399; hg19: chr4-15565018; COSMIC: COSV101052621; COSMIC: COSV101052621; API