NM_194248.3:c.4228-1G>T

Variant names:

• chr2-26467234-C-A
• rs111033342
• NM_194248.3:c.4228-1G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_194248.3(OTOF):​c.4228-1G>T variant causes a splice acceptor, intron change. The variant allele was found at a frequency of 0.00000889 in 1,461,868 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000089 (0 hom.)
• Consequence: OTOF NM_194248.3 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.11
• Publications: 1 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_pathogenic. The variant received 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.022522522 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 2-26467234-C-A is Pathogenic according to our data. Variant chr2-26467234-C-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2691708.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_194248.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OTOF	NM_194248.3	MANE Select	c.4228-1G>T		splice_acceptor intron	N/A	NP_919224.1
	OTOF	NM_194323.3	MANE Plus Clinical	c.1927-1G>T		splice_acceptor intron	N/A	NP_919304.1
	OTOF	NM_001287489.2		c.4228-1G>T		splice_acceptor intron	N/A	NP_001274418.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OTOF	ENST00000272371.7	TSL:1 MANE Select	c.4228-1G>T		splice_acceptor intron	N/A	ENSP00000272371.2
	OTOF	ENST00000339598.8	TSL:1 MANE Plus Clinical	c.1927-1G>T		splice_acceptor intron	N/A	ENSP00000344521.3
	OTOF	ENST00000402415.8	TSL:1	c.1987-1G>T		splice_acceptor intron	N/A	ENSP00000383906.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000795 AC: 2 AN: 251458 AF XY: 0.0000147

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000889 AC: 13 AN: 1461868 Hom.: 0 Cov.: 35 AF XY: 0.0000110 AC XY: 8 AN XY: 727236

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53394

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000117 AC: 13 AN: 1112012

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Nonsyndromic genetic hearing loss Pathogenic:1

Dec 14, 2023

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: OTOF c.4228-1G>T is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: four predict the variant abolishes a 3' acceptor site. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 8e-06 in 251458 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.4228-1G>T in individuals affected with Nonsyndromic Hearing Loss And Deafness, Type 9 and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have reported clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as likely pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Uncertain	0.035	T
BayesDel_noAF	Benign	-0.17
CADD	Pathogenic	34
DANN	Benign	0.88
Eigen	Uncertain	0.60
Eigen_PC	Uncertain	0.37
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		6.1
GERP RS		2.6
Mutation Taster		=3/97	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.76
SpliceAI score (max)		1.0		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.98		Position offset: -14
DS_AL_spliceai		1.0		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs111033342; hg19: chr2-26690102; COSMIC: COSV99716088; COSMIC: COSV99716088;