NM_181426.2:c.1665+1G>T

Variant names:

• chr3-180644119-C-A
• rs753580394
• NM_181426.2:c.1665+1G>T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PVS1_Moderate PM2

The NM_181426.2(CCDC39):​c.1665+1G>T variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000144 in 1,385,634 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CCDC39 NM_181426.2 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.86
• Publications: 0 publications found

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]

CCDC39 Gene-Disease associations (from GenCC):

• primary ciliary dyskinesia 14

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000145075 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.04883227 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_181426.2. 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
	CCDC39	NM_181426.2	MANE Select	c.1665+1G>T		splice_donor intron	N/A	NP_852091.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CCDC39	ENST00000476379.6	TSL:2 MANE Select	c.1665+1G>T		splice_donor intron	N/A	ENSP00000417960.2
	CCDC39	ENST00000650889.1		n.4878G>T		non_coding_transcript_exon	Exon 12 of 12
	CCDC39	ENST00000651818.1		n.1616G>T		non_coding_transcript_exon	Exon 12 of 12

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000144 AC: 2 AN: 1385634 Hom.: 0 Cov.: 28 AF XY: 0.00000293 AC XY: 2 AN XY: 682874

African (AFR) AF: 0.00 AC: 0 AN: 31050

American (AMR) AF: 0.00 AC: 0 AN: 33520

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 24928

East Asian (EAS) AF: 0.00 AC: 0 AN: 35318

South Asian (SAS) AF: 0.00 AC: 0 AN: 75418

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 48136

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5662

European-Non Finnish (NFE) AF: 0.00000186 AC: 2 AN: 1074120

Other (OTH) AF: 0.00 AC: 0 AN: 57482

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.26
CADD	Pathogenic	30
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		4.9
GERP RS		5.6
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.41		Position offset: 12
DS_DL_spliceai		0.99		Position offset: 1

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

Other links and lift over

dbSNP: rs753580394; hg19: chr3-180361907;