3-180651532-AC-A

Position:

• chr3-180651532-AC-A

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_181426.2(CCDC39):​c.1035del​(p.Arg345SerfsTer11) variant causes a frameshift, splice region change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CCDC39 NM_181426.2 frameshift, splice_region
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.774

Genes affected

CCDC39 (HGNC:25244): (coiled-coil domain 39 molecular ruler complex subunit) The protein encoded by this gene is involved in the motility of cilia and flagella. The encoded protein is essential for the assembly of dynein regulatory and inner dynein arm complexes, which regulate ciliary beat. Defects in this gene are a cause of primary ciliary dyskinesia type 14 (CILD14). [provided by RefSeq, Jul 2011]

ACMG classification

Verdict is Pathogenic. Variant got 12 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 3-180651532-AC-A is Pathogenic according to our data. Variant chr3-180651532-AC-A is described in ClinVar as [Pathogenic]. Clinvar id is 455008.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CCDC39	NM_181426.2	c.1035del	p.Arg345SerfsTer11	frameshift_variant, splice_region_variant	9/20	ENST00000476379.6	NP_852091.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CCDC39	ENST00000476379.6	c.1035del	p.Arg345SerfsTer11	frameshift_variant, splice_region_variant	9/20	2	NM_181426.2	ENSP00000417960	P2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 29

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 18, 2023

For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 455008). This variant has not been reported in the literature in individuals affected with CCDC39-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Arg345Serfs*11) in the CCDC39 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CCDC39 are known to be pathogenic (PMID: 21131972, 23255504). -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.91		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.51		Position offset: 0
DS_AL_spliceai		0.91		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs1553804640; hg19: chr3-180369320;