17-80099612-C-A

Position:

• chr17-80099612-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_017950.4(CCDC40):​c.3266C>A​(p.Ser1089Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,488 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CCDC40 NM_017950.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.968

Genes affected

CCDC40 (HGNC:26090): (coiled-coil domain 40 molecular ruler complex subunit) This gene encodes a protein that is necessary for motile cilia function. It functions in correct left-right axis formation by regulating the assembly of the inner dynein arm and the dynein regulatory complexes, which control ciliary beat. Mutations in this gene cause ciliary dyskinesia type 15, a disorder due to defects in cilia motility. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Aug 2011]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.22729832).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CCDC40	NM_017950.4	c.3266C>A	p.Ser1089Tyr	missense_variant	20/20	ENST00000397545.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CCDC40	ENST00000397545.9	c.3266C>A	p.Ser1089Tyr	missense_variant	20/20	5	NM_017950.4	P2
CCDC40	ENST00000574799.5	n.2803C>A		non_coding_transcript_exon_variant	16/16	1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461488 Hom.: 0 Cov.: 36 AF XY: 0.00000138 AC XY: 1 AN XY: 727054

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 06, 2018

This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with CCDC40-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This sequence change replaces serine with tyrosine at codon 1089 of the CCDC40 protein (p.Ser1089Tyr). The serine residue is moderately conserved and there is a large physicochemical difference between serine and tyrosine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.37
BayesDel_addAF	Benign	-0.090	T
BayesDel_noAF	Benign	-0.37
CADD	Benign	18
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.50	D
Eigen	Benign	-0.19
Eigen_PC	Benign	-0.40
FATHMM_MKL	Benign	0.075	N
LIST_S2	Benign	0.69	T
M_CAP	Benign	0.049	D
MetaRNN	Benign	0.23	T
MetaSVM	Benign	-0.90	T
MutationAssessor	Uncertain	2.2	M
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.37	T
PROVEAN	Uncertain	-3.7	D
REVEL	Benign	0.11
Sift	Uncertain	0.0060	D
Sift4G	Uncertain	0.0070	D
Polyphen		0.98	D
Vest4		0.20
MutPred		0.37		Loss of disorder (P = 0.0707);
MVP		0.54
MPC		0.78
ClinPred		0.95	D
GERP RS		1.4
Varity_R		0.17
gMVP		0.34

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

Publications

LitVar

Other links and lift over

dbSNP: rs762447884; hg19: chr17-78073411;