2-26457764-G-A

Variant names:

• chr2-26457764-G-A
• rs1664255863
• NM_194248.3:c.*474C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_194248.3(OTOF):​c.*474C>T variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000688 in 290,858 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: 33)
  • Exomes 𝑓: 0.0000069 (0 hom.)
• Consequence: OTOF NM_194248.3 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -2.11
• Publications: 0 publications found

Genes affected

OTOF (HGNC:8515): (otoferlin) Mutations in this gene are a cause of neurosensory nonsyndromic recessive deafness, DFNB9. The short form of the encoded protein has 3 C2 domains, a single carboxy-terminal transmembrane domain found also in the C. elegans spermatogenesis factor FER-1 and human dysferlin, while the long form has 6 C2 domains. The homology suggests that this protein may be involved in vesicle membrane fusion. Several transcript variants encoding multiple isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

OTOF Gene-Disease associations (from GenCC):

• autosomal recessive nonsyndromic hearing loss 9

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), G2P
• hearing loss, autosomal recessive

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.86).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
OTOF	NM_194248.3	c.*474C>T		3_prime_UTR_variant	Exon 47 of 47	ENST00000272371.7	NP_919224.1
OTOF	NM_194323.3	c.*276C>T		3_prime_UTR_variant	Exon 29 of 29	ENST00000339598.8	NP_919304.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
OTOF	ENST00000272371.7	c.*474C>T		3_prime_UTR_variant	Exon 47 of 47	1	NM_194248.3	ENSP00000272371.2
OTOF	ENST00000339598.8	c.*276C>T		3_prime_UTR_variant	Exon 29 of 29	1	NM_194323.3	ENSP00000344521.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000688 AC: 2 AN: 290858 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 150424

African (AFR) AF: 0.00 AC: 0 AN: 9388

American (AMR) AF: 0.0000910 AC: 1 AN: 10994

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 9676

East Asian (EAS) AF: 0.00 AC: 0 AN: 21204

South Asian (SAS) AF: 0.00 AC: 0 AN: 23636

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 17982

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 1414

European-Non Finnish (NFE) AF: 0.00000559 AC: 1 AN: 178830

Other (OTH) AF: 0.00 AC: 0 AN: 17734

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal recessive nonsyndromic hearing loss 9 Uncertain:1

Jan 12, 2018

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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
BayesDel_noAF	Benign	-0.86
CADD	Benign	1.7
DANN	Benign	0.32
PhyloP100		-2.1

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: rs1664255863; hg19: chr2-26680632;