4-15473257-T-C

Variant names:

• chr4-15473257-T-C
• rs568331446
• NM_001378615.1:c.-18-2658T>C

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_001080522.2(CC2D2A):​c.-19+2T>C variant causes a splice donor, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CC2D2A NM_001080522.2 splice_donor, intron
• Scores: Splicing: ADA: 0.7718
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.256

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 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 7.4, offset of 4, new splice context is: caaGTatgt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CC2D2A	NM_001378615.1	c.-18-2658T>C		intron_variant	Intron 1 of 36	ENST00000424120.6	NP_001365544.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CC2D2A	ENST00000424120.6	c.-18-2658T>C		intron_variant	Intron 1 of 36	5	NM_001378615.1	ENSP00000403465.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	4.7
DANN	Benign	0.80

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.77
dbscSNV1_RF	Benign	0.51
SpliceAI score (max)		0.0		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: rs568331446; hg19: chr4-15474881;