3-191382806-A-C

Variant names:

• chr3-191382806-A-C
• rs1553844770
• NM_178335.3:c.1303A>C

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2 BP4

The NM_178335.3(CCDC50):​c.1303A>C​(p.Lys435Gln) variant causes a missense change. The variant allele was found at a frequency of 0.000000685 in 1,460,376 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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: CCDC50 NM_178335.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 4.84
• Publications: 0 publications found

Genes affected

CCDC50 (HGNC:18111): (coiled-coil domain containing 50) This gene encodes a soluble, cytoplasmic, tyrosine-phosphorylated protein with multiple ubiquitin-interacting domains. Mutations in this gene cause nonsyndromic, postlingual, progressive sensorineural DFNA44 hearing loss. In mouse, the protein is expressed in the inner ear during development and postnatal maturation and associates with microtubule-based structures. This protein may also function as a negative regulator of NF-kB signaling and as an effector of epidermal growth factor (EGF)-mediated cell signaling. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Oct 2008]

CCDC50 Gene-Disease associations (from GenCC):

• autosomal dominant nonsyndromic hearing loss 44

  Inheritance: AD, Unknown Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), PanelApp Australia
• autosomal dominant nonsyndromic hearing loss

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• nonsyndromic genetic hearing loss

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.3237425).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CCDC50	NM_178335.3	c.1303A>C	p.Lys435Gln	missense_variant	Exon 10 of 12	ENST00000392455.9	NP_848018.1
CCDC50	NM_174908.4	c.775A>C	p.Lys259Gln	missense_variant	Exon 9 of 11		NP_777568.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CCDC50	ENST00000392455.9	c.1303A>C	p.Lys435Gln	missense_variant	Exon 10 of 12	1	NM_178335.3	ENSP00000376249.4
CCDC50	ENST00000392456.4	c.775A>C	p.Lys259Gln	missense_variant	Exon 9 of 11	1		ENSP00000376250.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460376 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726566

African (AFR) AF: 0.00 AC: 0 AN: 33416

American (AMR) AF: 0.00 AC: 0 AN: 44704

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26096

East Asian (EAS) AF: 0.00 AC: 0 AN: 39650

South Asian (SAS) AF: 0.00 AC: 0 AN: 86230

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53400

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1110806

Other (OTH) AF: 0.00 AC: 0 AN: 60314

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

May 18, 2018

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant classified as Uncertain Significance - Favor Benign. The p.Lys435Gln var iant in CCDC50 has been identified in 1 individual with hearing loss by our labo ratory; however, it did not segregate in an affected parent. This variant was ab sent from large population studies. Computational prediction tools and conservat ion analysis do not provide strong support for or against an impact to the prote in. In summary, while the clinical significance of the p.Lys435Gln variant is un certain, the non-segregation suggests it is more likely to be benign. ACMG/AMP C riteria applied: BS4_Supporting, PM2. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	-0.077	T
BayesDel_noAF	Benign	-0.35
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.063	.;T
Eigen	Pathogenic	0.70
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.74	T;T
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.32	T;T
MetaSVM	Benign	-0.73	T
MutationAssessor	Uncertain	2.5	.;M
PhyloP100		4.8
PrimateAI	Benign	0.43	T
REVEL	Benign	0.16
Polyphen		0.99	D;D
MutPred		0.30		.;Loss of ubiquitination at K259 (P = 0.0022);
MVP		0.57
MPC		0.57
ClinPred		0.93	D
GERP RS		6.2
Varity_R		0.12
gMVP		0.051
Mutation Taster		=94/6	polymorphism

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: rs1553844770; hg19: chr3-191100595;