chr1-68429787-TG-T

Position:

• chr1-68429787-TG-T

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_000329.3(RPE65):​c.1590delC​(p.Phe530fs) variant causes a frameshift change. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: RPE65 NM_000329.3 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:2 O:1
• Conservation: PhyloP100: 6.55

Genes affected

RPE65 (HGNC:10294): (retinoid isomerohydrolase RPE65) The protein encoded by this gene is a component of the vitamin A visual cycle of the retina which supplies the 11-cis retinal chromophore of the photoreceptors opsin visual pigments. It is a member of the carotenoid cleavage oxygenase superfamily. All members of this superfamily are non-heme iron oxygenases with a seven-bladed propeller fold and oxidatively cleave carotenoid carbon:carbon double bonds. However, the protein encoded by this gene has acquired a divergent function that involves the concerted O-alkyl ester cleavage of its all-trans retinyl ester substrate and all-trans to 11-cis double bond isomerization of the retinyl moiety. As such, it performs the essential enzymatic isomerization step in the synthesis of 11-cis retinal. Mutations in this gene are associated with early-onset severe blinding disorders such as Leber congenital. [provided by RefSeq, Oct 2017]

LOC124904198 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 14 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. There are 5 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 1-68429787-TG-T is Pathogenic according to our data. Variant chr1-68429787-TG-T is described in ClinVar as [Pathogenic]. Clinvar id is 98850.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-68429787-TG-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RPE65	NM_000329.3	c.1590delC	p.Phe530fs	frameshift_variant	14/14	ENST00000262340.6	NP_000320.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RPE65	ENST00000262340.6	c.1590delC	p.Phe530fs	frameshift_variant	14/14	1	NM_000329.3	ENSP00000262340.5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Leber congenital amaurosis 2;C3151086:Retinitis pigmentosa 20 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 28, 2023

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 98850). This frameshift has been observed in individual(s) with clinical features of RPE65-related conditions (PMID: 16505055, 19854499, 30268864). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is not present in population databases (gnomAD no frequency). This sequence change results in a frameshift in the RPE65 gene (p.Phe530Leufs*40). While this is not anticipated to result in nonsense mediated decay, it is expected to disrupt the last 4 amino acid(s) of the RPE65 protein and extend the protein by 35 additional amino acid residues. -

Leber congenital amaurosis 2 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Baylor Genetics

Dec 16, 2021

- -

not provided Other:1

not provided, no classification provided

literature only

Retina International

-

- -

Computational scores

Source: dbNSFP v4.3

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: rs281865292; hg19: chr1-68895470;