rs773033304

chr17-80099591-G-A

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_Strong BP6

The NM_017950.4(CCDC40):c.3245G>A(p.Arg1082His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000116 in 1,613,388 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1082C) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000066 (1 hom., cov: 32)
  • Exomes 𝑓: 0.00012 (2 hom.)
• Consequence: CCDC40 NM_017950.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 1.36

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 Likely_benign. Variant got -5 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.036580265).
• BP6: Variant 17-80099591-G-A is Benign according to our data. Variant chr17-80099591-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 325748.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=2}.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CCDC40	NM_017950.4	c.3245G>A	p.Arg1082His	missense_variant	20/20	ENST00000397545.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CCDC40	ENST00000397545.9	c.3245G>A	p.Arg1082His	missense_variant	20/20	5	NM_017950.4	P2
CCDC40	ENST00000574799.5	n.2782G>A		non_coding_transcript_exon_variant	16/16	1

Frequencies

GnomAD3 genomes AF: 0.0000657 AC: 10 AN: 152196 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00165

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.000478

GnomAD3 exomes AF: 0.000237 AC: 59 AN: 248934 Hom.: 0 AF XY: 0.000340 AC XY: 46 AN XY: 135178

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00186

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000177

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000121 AC: 177 AN: 1461192 Hom.: 2 Cov.: 36 AF XY: 0.000182 AC XY: 132 AN XY: 726912

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: 0.00194

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000630

Gnomad4 OTH exome AF: 0.0000497

GnomAD4 genome AF: 0.0000657 AC: 10 AN: 152196 Hom.: 1 Cov.: 32 AF XY: 0.000121 AC XY: 9 AN XY: 74362

Gnomad4 AFR AF: 0.0000241

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00165

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.000478

Bravo AF: 0.0000113

ExAC AF: 0.000265 AC: 32

Asia WGS AF: 0.000577 AC: 2 AN: 3478

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Primary ciliary dyskinesia Uncertain:1 Benign:1

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Aug 09, 2022	This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 1082 of the CCDC40 protein (p.Arg1082His). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with CCDC40-related conditions. ClinVar contains an entry for this variant (Variation ID: 325748). 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. -
Likely benign, criteria provided, single submitter	clinical testing	Ambry Genetics	May 22, 2023	This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Primary ciliary dyskinesia 15 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 12, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.50	T
BayesDel_noAF	Benign	-0.50
Cadd	Uncertain	24
Dann	Uncertain	1.0
DEOGEN2	Benign	0.39	T
Eigen	Benign	-0.088
Eigen_PC	Benign	-0.26
FATHMM_MKL	Benign	0.18	N
LIST_S2	Uncertain	0.88	D
M_CAP	Benign	0.039	D
MetaRNN	Benign	0.037	T
MetaSVM	Benign	-0.92	T
MutationAssessor	Benign	1.8	L
MutationTaster	Benign	1.0	N
PrimateAI	Benign	0.35	T
PROVEAN	Uncertain	-3.0	D
REVEL	Benign	0.089
Sift	Uncertain	0.0070	D
Sift4G	Uncertain	0.045	D
Polyphen		1.0	D
Vest4		0.12
MutPred		0.34		Loss of MoRF binding (P = 0.0123);
MVP		0.42
MPC		0.75
ClinPred		0.24	T
GERP RS		0.52
Varity_R		0.092
gMVP		0.21

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs773033304; hg19: chr17-78073390; COSMIC: COSV56408550; COSMIC: COSV56408550;