1-197435035-G-T

Position:

• chr1-197435035-G-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_201253.3(CRB1):​c.3172G>T​(p.Glu1058*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CRB1 NM_201253.3 stop_gained
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:6
• Conservation: PhyloP100: 1.85

Genes affected

CRB1 (HGNC:2343): (crumbs cell polarity complex component 1) This gene encodes a protein which is similar to the Drosophila crumbs protein and localizes to the inner segment of mammalian photoreceptors. In Drosophila crumbs localizes to the stalk of the fly photoreceptor and may be a component of the molecular scaffold that controls proper development of polarity in the eye. Mutations in this gene are associated with a severe form of retinitis pigmentosa, RP12, and with Leber congenital amaurosis. Alternate splicing results in multiple transcript variants, some protein coding and some non-protein coding.[provided by RefSeq, Apr 2012]

CRB1 (HGNC:):

ACMG classification

Verdict is Pathogenic. Variant got 18 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
• PP5: Variant 1-197435035-G-T is Pathogenic according to our data. Variant chr1-197435035-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 521051.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr1-197435035-G-T is described in Lovd as [Pathogenic]. Variant chr1-197435035-G-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CRB1	NM_201253.3	c.3172G>T	p.Glu1058*	stop_gained	9/12	ENST00000367400.8	NP_957705.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CRB1	ENST00000367400.8	c.3172G>T	p.Glu1058*	stop_gained	9/12	1	NM_201253.3	ENSP00000356370.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Leber congenital amaurosis 8 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	Baylor Genetics	Mar 13, 2024	- -

Inborn genetic diseases Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

May 05, 2016

- -

Retinitis pigmentosa 12;C3151202:Leber congenital amaurosis 8 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 14, 2022

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 521051). This variant has not been reported in the literature in individuals affected with CRB1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Glu1058*) in the CRB1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in CRB1 are known to be pathogenic (PMID: 10508521, 22065545, 23379534, 25412400, 26957898, 28041643, 29391521). -

Retinitis pigmentosa 12 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Apr 11, 2023

- -

Stargardt disease Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+

Sep 01, 2016

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	34
DANN	Uncertain	0.98
Eigen	Benign	0.073
Eigen_PC	Benign	-0.20
FATHMM_MKL	Benign	0.10	N
Vest4		0.92
GERP RS		4.8

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: rs564754426; hg19: chr1-197404165;