2-26463970-G-C

Position:

• chr2-26463970-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM1 PM2

The NM_194248.3(OTOF):​c.5097C>G​(p.Ile1699Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. I1699I) has been classified as Benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: OTOF NM_194248.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.565

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_194248.3
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
OTOF	NM_194248.3	c.5097C>G	p.Ile1699Met	missense_variant	40/47	ENST00000272371.7
OTOF	NM_194323.3	c.2796C>G	p.Ile932Met	missense_variant	23/29	ENST00000339598.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
OTOF	ENST00000272371.7	c.5097C>G	p.Ile1699Met	missense_variant	40/47	1	NM_194248.3	A1
OTOF	ENST00000339598.8	c.2796C>G	p.Ile932Met	missense_variant	23/29	1	NM_194323.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Autosomal recessive nonsyndromic hearing loss 9 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 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	0.16
BayesDel_addAF	Uncertain	0.14	D
BayesDel_noAF	Uncertain	-0.040
CADD	Benign	17
DANN	Uncertain	0.99
DEOGEN2	Benign	0.13	.;.;.;T;.;.
Eigen	Benign	-0.29
Eigen_PC	Benign	-0.33
FATHMM_MKL	Benign	0.63	D
LIST_S2	Uncertain	0.88	D;D;D;D;D;D
M_CAP	Uncertain	0.089	D
MetaRNN	Uncertain	0.71	D;D;D;D;D;D
MetaSVM	Uncertain	-0.0076	T
MutationAssessor	Uncertain	2.0	.;.;.;M;M;.
MutationTaster	Benign	0.00025	P;P;P;P;P
PrimateAI	Uncertain	0.74	T
PROVEAN	Benign	-1.5	N;N;.;N;N;.
REVEL	Uncertain	0.64
Sift	Benign	0.41	T;T;.;T;T;.
Sift4G	Benign	0.43	T;T;.;T;T;.
Polyphen		0.063	B;B;.;D;.;D
Vest4		0.51
MutPred		0.42		.;.;.;Gain of disorder (P = 0.0212);Gain of disorder (P = 0.0212);.;
MVP		0.83
MPC		0.60
ClinPred		0.84	D
GERP RS		-1.6
Varity_R		0.17
gMVP		0.71

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

Publications

LitVar

Other links and lift over

dbSNP: rs12386239; hg19: chr2-26686838;