NM_001378615.1:c.1946C>G

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2BP4_StrongBP6

The NM_001378615.1(CC2D2A):​c.1946C>G​(p.Thr649Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000343 in 1,605,692 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T649M) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000034 ( 0 hom. )

Consequence

CC2D2A
NM_001378615.1 missense

Scores

1
18

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:1

Conservation

PhyloP100: -0.933

Publications

1 publications found
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 Gene-Disease associations (from GenCC):
  • ciliopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • Joubert syndrome 9
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, G2P
  • retinitis pigmentosa 93
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
  • COACH syndrome 1
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Joubert syndrome with oculorenal defect
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • Meckel syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -3 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.02669996).
BP6
Variant 4-15538080-C-G is Benign according to our data. Variant chr4-15538080-C-G is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 347761.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CC2D2ANM_001378615.1 linkc.1946C>G p.Thr649Arg missense_variant Exon 16 of 37 ENST00000424120.6 NP_001365544.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CC2D2AENST00000424120.6 linkc.1946C>G p.Thr649Arg missense_variant Exon 16 of 37 5 NM_001378615.1 ENSP00000403465.1 Q9P2K1-4

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152094
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000554
AC:
13
AN:
234634
AF XY:
0.0000552
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000467
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000471
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000344
AC:
50
AN:
1453598
Hom.:
0
Cov.:
33
AF XY:
0.0000305
AC XY:
22
AN XY:
722030
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33364
American (AMR)
AF:
0.00
AC:
0
AN:
43650
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25874
East Asian (EAS)
AF:
0.000152
AC:
6
AN:
39386
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84336
European-Finnish (FIN)
AF:
0.0000189
AC:
1
AN:
52926
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5756
European-Non Finnish (NFE)
AF:
0.0000379
AC:
42
AN:
1108190
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.506
Heterozygous variant carriers
0
3
7
10
14
17
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000329
AC:
5
AN:
152094
Hom.:
0
Cov.:
32
AF XY:
0.0000538
AC XY:
4
AN XY:
74290
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41426
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5176
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10588
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.495
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000680
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000660
AC:
8

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:3Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Dec 03, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1946C>G (p.T649R) alteration is located in exon 17 (coding exon 15) of the CC2D2A gene. This alteration results from a C to G substitution at nucleotide position 1946, causing the threonine (T) at amino acid position 649 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Meckel syndrome, type 6 Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Joubert syndrome 9 Uncertain:1
Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Meckel-Gruber syndrome;C0431399:Joubert syndrome Benign:1
Feb 02, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.076
BayesDel_addAF
Benign
-0.37
T
BayesDel_noAF
Benign
-0.44
CADD
Benign
0.83
DANN
Benign
0.85
DEOGEN2
Benign
0.19
T;T
Eigen
Benign
-1.3
Eigen_PC
Benign
-1.4
FATHMM_MKL
Benign
0.083
N
LIST_S2
Uncertain
0.92
D;.
M_CAP
Benign
0.029
D
MetaRNN
Benign
0.027
T;T
MetaSVM
Benign
-0.98
T
MutationAssessor
Benign
0.34
N;N
PhyloP100
-0.93
PrimateAI
Benign
0.23
T
PROVEAN
Benign
-1.7
N;N
REVEL
Benign
0.14
Sift
Benign
0.095
T;T
Sift4G
Benign
0.17
T;T
Polyphen
0.55
P;P
Vest4
0.14
MVP
0.12
MPC
0.047
ClinPred
0.13
T
GERP RS
-8.9
Varity_R
0.18
gMVP
0.46
Mutation Taster
=94/6
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.17
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs201884883; hg19: chr4-15539703; API