16-21678534-CAT-C

Variant names:

• chr16-21678534-CAT-C
• rs1223258366
• NM_144672.4:c.22_23delTA

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_144672.4(OTOA):​c.22_23delTA​(p.Tyr8LeufsTer59) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,613,632 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. Y8Y) has been classified as Likely benign.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: OTOA NM_144672.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 0.0310
• Publications: 0 publications found

Genes affected

OTOA (HGNC:16378): (otoancorin) The protein encoded by this gene is specifically expressed in the inner ear, and is located at the interface between the apical surface of the inner ear sensory epithelia and their overlying acellular gels. It is prposed that this protein is involved in the attachment of the inner ear acellular gels to the apical surface of the underlying nonsensory cells. Mutations in this gene are associated with autosomal recessive deafness type 22 (DFNB22). Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Sep 2009]

OTOA Gene-Disease associations (from GenCC):

• autosomal recessive nonsyndromic hearing loss 22

  Inheritance: AR Classification: DEFINITIVE, STRONG, LIMITED Submitted by: Laboratory for Molecular Medicine, G2P, PanelApp Australia, Labcorp Genetics (formerly Invitae)
• nonsyndromic genetic hearing loss

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• hearing loss, autosomal recessive

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 68 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-21678534-CAT-C is Pathogenic according to our data. Variant chr16-21678534-CAT-C is described in ClinVar as [Pathogenic]. Clinvar id is 2820890.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
OTOA	NM_144672.4	c.22_23delTA	p.Tyr8LeufsTer59	frameshift_variant	Exon 2 of 29	ENST00000646100.2	NP_653273.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
OTOA	ENST00000646100.2	c.22_23delTA	p.Tyr8LeufsTer59	frameshift_variant	Exon 2 of 29		NM_144672.4	ENSP00000496564.2
OTOA	ENST00000388958.8	c.22_23delTA	p.Tyr8LeufsTer59	frameshift_variant	Exon 1 of 28	1		ENSP00000373610.3
OTOA	ENST00000286149.8	c.22_23delTA	p.Tyr8LeufsTer59	frameshift_variant	Exon 1 of 28	5		ENSP00000286149.4
OTOA	ENST00000647277.1	n.22_23delTA		non_coding_transcript_exon_variant	Exon 2 of 29			ENSP00000495594.1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151946 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461686 Hom.: 0 AF XY: 0.00000413 AC XY: 3 AN XY: 727150

African (AFR) AF: 0.00 AC: 0 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39664

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

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

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000630 AC: 7 AN: 1111892

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 151946 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74202

African (AFR) AF: 0.00 AC: 0 AN: 41348

American (AMR) AF: 0.00 AC: 0 AN: 15210

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.00 AC: 0 AN: 5186

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10570

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68016

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Aug 05, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Tyr8Leufs*59) in the OTOA gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in OTOA are known to be pathogenic (PMID: 11972037). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with OTOA-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		0.031
Mutation Taster		=113/87	disease causing (fs/PTC)

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: rs1223258366; hg19: chr16-21689855;