NM_021147.5:c.787C>A

Variant names:

• chr5-55231641-G-T
• rs771099683
• NM_021147.5:c.787C>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_021147.5(CCNO):​c.787C>A​(p.Arg263Arg) variant causes a synonymous 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. R263R) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: CCNO NM_021147.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.34
• Publications: 0 publications found

Genes affected

CCNO (HGNC:18576): (cyclin O) This gene encodes a member of the cyclin protein family, and the encoded protein is involved in regulation of the cell cycle. Disruption of this gene is associated with primary ciliary dyskinesia-19. Alternative splicing results in multiple transcript variants. This gene, which has a previous symbol of UNG2, was erroneously identified as a uracil DNA glycosylase in PubMed ID: 2001396. A later publication, PubMed ID: 8419333, identified this gene's product as a cyclin protein family member. The UNG2 symbol is also used as a specific protein isoform name for the UNG gene (GeneID 7374), so confusion exists in the scientific literature and in some databases for these two genes. [provided by RefSeq, Jul 2014]

CCNO Gene-Disease associations (from GenCC):

• primary ciliary dyskinesia 29

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: G2P, Labcorp Genetics (formerly Invitae), PanelApp Australia, ClinGen, Ambry Genetics
• primary ciliary dyskinesia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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 (BayesDel_noAF=-0.8).
• BP7: Synonymous conserved (PhyloP=1.34 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_021147.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CCNO	NM_021147.5	MANE Select	c.787C>A	p.Arg263Arg	synonymous	Exon 3 of 3	NP_066970.3
	CCNO	NR_125346.2		n.1248C>A		non_coding_transcript_exon	Exon 3 of 3
	CCNO	NR_125347.2		n.877C>A		non_coding_transcript_exon	Exon 3 of 3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CCNO	ENST00000282572.5	TSL:1 MANE Select	c.787C>A	p.Arg263Arg	synonymous	Exon 3 of 3	ENSP00000282572.4
	CCNO	ENST00000501463.2	TSL:1	n.*767C>A		non_coding_transcript_exon	Exon 3 of 3	ENSP00000422485.1
	CCNO	ENST00000501463.2	TSL:1	n.*767C>A		3_prime_UTR	Exon 3 of 3	ENSP00000422485.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	8.2
DANN	Benign	0.67
PhyloP100		1.3

Splicing

Name	Calibrated prediction	Score	Prediction
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

Other links and lift over

dbSNP: rs771099683; hg19: chr5-54527469;