NM_021728.4:c.191_193delTGTinsGG

Variant names:

• chr14-56804268-ACA-CC
• rs1555350397
• NM_021728.4:c.191_193delTGTinsGG

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 13P and 0B. PVS1 PM2 PP2 PP5_Moderate

The NM_021728.4(OTX2):​c.191_193delTGTinsGG​(p.Leu64ArgfsTer18) variant causes a frameshift, missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. L64L) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: OTX2 NM_021728.4 frameshift, missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.31
• Publications: 0 publications found

Genes affected

OTX2 (HGNC:8522): (orthodenticle homeobox 2) This gene encodes a member of the bicoid subfamily of homeodomain-containing transcription factors. The encoded protein acts as a transcription factor and plays a role in brain, craniofacial, and sensory organ development. The encoded protein also influences the proliferation and differentiation of dopaminergic neuronal progenitor cells during mitosis. Mutations in this gene cause syndromic microphthalmia 5 (MCOPS5) and combined pituitary hormone deficiency 6 (CPHD6). This gene is also suspected of having an oncogenic role in medulloblastoma. Alternative splicing results in multiple transcript variants encoding distinct isoforms. Pseudogenes of this gene are known to exist on chromosomes two and nine. [provided by RefSeq, Jul 2012]

OTX2 Gene-Disease associations (from GenCC):

• syndromic microphthalmia type 5

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), PanelApp Australia, Ambry Genetics, Orphanet
• pituitary hormone deficiency, combined, 6

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
• combined pituitary hormone deficiencies, genetic form

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• isolated anophthalmia-microphthalmia syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• patterned macular dystrophy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• septooptic dysplasia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 13 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 10 curated pathogenic missense variants (we use a threshold of 10). The gene has 1 curated benign missense variants. Gene score misZ: 1.0457 (below the threshold of 3.09). Trascript score misZ: 1.6551 (below the threshold of 3.09). GenCC associations: The gene is linked to syndromic microphthalmia type 5, combined pituitary hormone deficiencies, genetic form, pituitary hormone deficiency, combined, 6, isolated anophthalmia-microphthalmia syndrome, septooptic dysplasia, patterned macular dystrophy.
• PP5: Variant 14-56804268-ACA-CC is Pathogenic according to our data. Variant chr14-56804268-ACA-CC is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 523565.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
OTX2	NM_021728.4	c.191_193delTGTinsGG	p.Leu64ArgfsTer18	frameshift_variant, missense_variant	Exon 4 of 5	ENST00000672264.2	NP_068374.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
OTX2	ENST00000672264.2	c.191_193delTGTinsGG	p.Leu64ArgfsTer18	frameshift_variant, missense_variant	Exon 4 of 5		NM_021728.4	ENSP00000500115.1

Frequencies

GnomAD3 genomes Cov.: 32

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Anxiety;C0026826:Hypertonia;C0028738:Nystagmus;C0239234:Low-set ears;C0271385:Horizontal nystagmus;C0424711:Hypotelorism;C0751466:Phonophobia;C1844505:Pointed chin;C1855285:Protruding ear Pathogenic:1

Jan 01, 2017

Centre for Mendelian Genomics, University Medical Centre Ljubljana

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.3

Splicing

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

Other links and lift over

dbSNP: rs1555350397; hg19: chr14-57270986;