1-68446824-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1PM2PM5PP3_StrongPP5_Very_Strong

The NM_000329.3(RPE65):​c.131G>A​(p.Arg44Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000143 in 1,613,952 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R44L) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

RPE65
NM_000329.3 missense

Scores

15
3
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:7O:1

Conservation

PhyloP100: 7.56
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 5 uncertain in NM_000329.3
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr1-68446824-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 2170981.Status of the report is criteria_provided_single_submitter, 1 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.99
PP5
Variant 1-68446824-C-T is Pathogenic according to our data. Variant chr1-68446824-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 98840.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-68446824-C-T is described in Lovd as [Pathogenic]. Variant chr1-68446824-C-T is described in Lovd as [Pathogenic]. Variant chr1-68446824-C-T is described in Lovd as [Likely_pathogenic]. Variant chr1-68446824-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
RPE65NM_000329.3 linkc.131G>A p.Arg44Gln missense_variant Exon 3 of 14 ENST00000262340.6 NP_000320.1 Q16518

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
RPE65ENST00000262340.6 linkc.131G>A p.Arg44Gln missense_variant Exon 3 of 14 1 NM_000329.3 ENSP00000262340.5 Q16518

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152172
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000398
AC:
10
AN:
251472
Hom.:
0
AF XY:
0.0000368
AC XY:
5
AN XY:
135910
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.000163
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000144
AC:
21
AN:
1461662
Hom.:
0
Cov.:
32
AF XY:
0.0000165
AC XY:
12
AN XY:
727132
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.0000447
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.000139
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000540
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152290
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74462
show subpopulations
Gnomad4 AFR
AF:
0.0000241
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.000208
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000496
Hom.:
0
Bravo
AF:
0.00000756
ExAC
AF:
0.0000576
AC:
7
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:7Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Leber congenital amaurosis 2 Pathogenic:2
-
Laboratory of Genetics in Ophthalmology, Institut Imagine
Significance: Likely pathogenic
Review Status: no assertion criteria provided
Collection Method: research

- -

Oct 04, 2023
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

RPE65-related disorder Pathogenic:1
Apr 20, 2023
PreventionGenetics, part of Exact Sciences
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The RPE65 c.131G>A variant is predicted to result in the amino acid substitution p.Arg44Gln. This variant in either homozygous state or along with a second causative variant, has been reported in patients with RPE65-associated disorders such as Leber congenital amaurosis (Simovich et al. 2001. PubMed ID: 11462243; Table S1, Patel. 2016. PubMed ID: 26355662; Cideciyan et al. 2008. PubMed ID: 18809924). Functional in vitro studies have shown that this variant resulted in a protein with reduced isomerization activity (~2% of wild-type activity) (Redmond. 2005. PubMed ID: 16150724; Philp. 2009. PubMed ID: 19431183). This variant is reported in 0.016% of alleles in individuals of South Asian descent in gnomAD (http://gnomad.broadinstitute.org/variant/1-68912507-C-T). This variant is interpreted as pathogenic. -

Autosomal recessive retinitis pigmentosa Pathogenic:1
Sep 10, 2015
Faculty of Health Sciences, Beirut Arab University
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Leber congenital amaurosis 2;C3151086:Retinitis pigmentosa 20 Pathogenic:1
Aug 02, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. Experimental studies have shown that this missense change affects RPE65 function (PMID: 16150724). This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 44 of the RPE65 protein (p.Arg44Gln). This variant is present in population databases (rs61751282, gnomAD 0.02%). This missense change has been observed in individual(s) with Leber's congenital amaurosis (PMID: 11462243, 15024725, 18539930, 19431183, 20079931). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 98840). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) has been performed at Invitae for this missense variant, however the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on RPE65 protein function. -

Leber congenital amaurosis Pathogenic:1
Sep 16, 2020
Natera, Inc.
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

Retinitis pigmentosa 20 Pathogenic:1
Jan 03, 2022
3billion
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Same nucleotide change resulting in same amino acid change has been previously reported to be associated with RPE65 related disorder (ClinVar ID: VCV000098840, PMID:11462243, PS1_P). The variant has been reported to be in trans with a pathogenic variant as either compound heterozygous or homozygous in at least one similarly affected unrelated individual (PMID: 11462243, 15024725, 20079931, PM3_M). Functional studies provide strong evidence of the variant having a damaging effect on the gene or gene product (PMID: 16150724, 19431183, PS3_S). In silico tool predictions suggest damaging effect of the variant on gene or gene product (REVEL: 0.971, 3CNET: 0.813, PP3_P). A missense variant is a common mechanism associated with Retinitis pigmentosa 20 (PP2_P). It is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: 0.000040, PM2_M).. Therefore, this variant is classified as pathogenic according to the recommendation of ACMG/AMP guideline. -

not provided Other:1
-
Retina International
Significance: not provided
Review Status: no classification provided
Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.89
BayesDel_addAF
Pathogenic
0.39
D
BayesDel_noAF
Pathogenic
0.58
CADD
Pathogenic
33
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.98
D
Eigen
Pathogenic
1.0
Eigen_PC
Pathogenic
0.96
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.99
D
M_CAP
Pathogenic
0.40
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.5
M
PrimateAI
Uncertain
0.70
T
PROVEAN
Uncertain
-3.6
D
REVEL
Pathogenic
0.97
Sift
Uncertain
0.0010
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.99
MutPred
0.98
Loss of methylation at R44 (P = 0.0391);
MVP
1.0
MPC
0.38
ClinPred
0.95
D
GERP RS
5.9
Varity_R
0.89
gMVP
0.95

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

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs61751282; hg19: chr1-68912507; COSMIC: COSV52013003; API