dbSNP rs748451478: CC2D2A:c.3014+4A>C (chr4-15560626-A-C) – ACMG Classification: Uncertain_significance (0 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001378615.1(CC2D2A):c.3014+4A>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000383 in 1,193,788 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00042 ( 0 hom. )

Consequence

CC2D2A
NM_001378615.1 splice_region, intron

Scores

Splicing: ADA: 0.1065

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 1.72

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]

CC2D2A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.45).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CC2D2A	NM_001378615.1 link	c.3014+4A>C		splice_region_variant, intron_variant	Intron 23 of 36	ENST00000424120.6	NP_001365544.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CC2D2A	ENST00000424120.6 link	c.3014+4A>C		splice_region_variant, intron_variant	Intron 23 of 36	5	NM_001378615.1	ENSP00000403465.1		Q9P2K1-4

Frequencies

GnomAD3 genomes

AF:

0.000131

AC:

AN:

152232

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000121

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000220

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000142

AC:

AN:

183704

Hom.:

AF XY:

0.000141

AC XY:

AN XY:

99404

show subpopulations

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:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.000305

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.000420

AC:

437

AN:

1041556

Hom.:

Cov.:

AF XY:

0.000408

AC XY:

217

AN XY:

531476

show subpopulations

Gnomad4 AFR exome

AF:

0.0000422

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:

0.000561

Gnomad4 OTH exome

AF:

0.000218

GnomAD4 genome

AF:

0.000131

AC:

AN:

152232

Hom.:

Cov.:

AF XY:

0.0000538

AC XY:

AN XY:

74380

show subpopulations

Gnomad4 AFR

AF:

0.000121

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000220

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000148

Hom.:

Bravo

AF:

0.000159

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

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

Uncertain:1

Sep 27, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change falls in intron 24 of the CC2D2A gene. It does not directly change the encoded amino acid sequence of the CC2D2A protein. It affects a nucleotide within the consensus splice site. This variant is present in population databases (rs748451478, gnomAD 0.03%). This variant has not been reported in the literature in individuals affected with CC2D2A-related conditions. ClinVar contains an entry for this variant (Variation ID: 391066). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant is not likely to affect RNA splicing. 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. -

Inborn genetic diseases

Uncertain:1

Aug 15, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.3014+4A>C intronic alteration consists of a A to C substitution nucleotides after coding exon 22 in the CC2D2A gene. Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Joubert syndrome 9;C2676790:Meckel syndrome, type 6;C5436837:COACH syndrome 2;C5676970:Retinitis pigmentosa 93

Uncertain:1

May 30, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified

Benign:1

Nov 18, 2016

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -

CC2D2A-related disorder

Benign:1

Sep 08, 2023

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.45

CADD

Benign

DANN

Benign

0.88

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Benign

0.11

dbscSNV1_RF

Benign

0.40

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

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over