Mendeliome
Gene: CRB1 Green List (high evidence)Green List (high evidence)
Multiple families published with recessive phenotypes, including RP, cone-rod dystrophy, LCA, PMIDs 33921607, 42376998, 34130719, 28800606, 41626423
Mono-allelic reports: PMID 41626423 describes over 30 patients with heterozygous variants, but no segregation data, hence Amber for this MOI.Created: 22 Jul 2026, 7:15 p.m. | Last Modified: 22 Jul 2026, 7:15 p.m.
Panel Version: 2.260
Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Phenotypes
Leber congenital amaurosis 8, MONDO:0013453; hereditary macular dystrophy, MONDO:0020242; inherited retinal dystrophy, MONDO:0019118; retinitis pigmentosa 12, MONDO:0010818
Publications
Red List (low evidence)
PMID: 15623792
Multiple individuals with PPCRA phenotype from the same family reported with heterozygous missense variant (Val162Met - GrpMax FAF 0.1789%).
No other families have been reported with AD association.Created: 19 May 2025, 2:09 p.m.
Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, NOT imprinted
Phenotypes
pigmented paravenous retinochoroidal atrophy MONDO:0008246
Publications
Green List (high evidence)
gene reviews:
CRB1 accounts for ~10% of LCA/EOSRD cases
No genotype-phenotype correlation has been specifically confirmed (PMID: 32922261). (PMID:15459956) suggests that LCA is due to complete CRB1 loss of function while RP (less severe, with later onset) has residual CRB1 function, however, no specific evidence clearly demonstrating this has been found, and has not been mentioned in recent reviews (PMIDs: 15459956, 32922261, 31884620).Created: 4 May 2022, 8:20 p.m.
Mode of inheritance
BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Phenotypes
Leber congenital amaurosis 8 MIM#613835; Pigmented paravenous chorioretinal atrophy MIM#172870; Retinitis pigmentosa-12 MIM#600105
Publications
Variants in this GENE are reported as part of current diagnostic practice
Publications for gene: CRB1 were set to 30285347; 32922261; 31884620; 15459956; 15623792
Mode of inheritance for gene: CRB1 was changed from BIALLELIC, autosomal or pseudoautosomal to BOTH monoallelic and biallelic, autosomal or pseudoautosomal
Publications for gene: CRB1 were set to 30285347; 32922261; 31884620; 15459956
Mode of inheritance for gene: CRB1 was changed from BOTH monoallelic and biallelic, autosomal or pseudoautosomal to BIALLELIC, autosomal or pseudoautosomal
Gene: crb1 has been classified as Green List (High Evidence).
Phenotypes for gene: CRB1 were changed from to Leber congenital amaurosis 8 MIM#613835; Pigmented paravenous chorioretinal atrophy MIM#172870; Retinitis pigmentosa-12 MIM#600105
Publications for gene: CRB1 were set to
Mode of inheritance for gene: CRB1 was changed from Unknown to BOTH monoallelic and biallelic, autosomal or pseudoautosomal
gene: CRB1 was added gene: CRB1 was added to Mendeliome_VCGS. Sources: Expert Review Green,Victorian Clinical Genetics Services Mode of inheritance for gene: CRB1 was set to Unknown
If promoting or demoting a gene, please provide comments to justify a decision to move it.
Genes included in a Genomics England gene panel for a rare disease category (green list) should fit the criteria A-E outlined below.
These guidelines were developed as a combination of the ClinGen DEFINITIVE evidence for a causal role of the gene in the disease(a), and the Developmental Disorder Genotype-Phenotype (DDG2P) CONFIRMED DD Gene evidence level(b) (please see the original references provided below for full details). These help provide a guideline for expert reviewers when assessing whether a gene should be on the green or the red list of a panel.
A. There are plausible disease-causing mutations(i) within, affecting or encompassing an interpretable functional region(ii) of this gene identified in multiple (>3) unrelated cases/families with the phenotype(iii).
OR
B. There are plausible disease-causing mutations(i) within, affecting or encompassing cis-regulatory elements convincingly affecting the expression of a single gene identified in multiple (>3) unrelated cases/families with the phenotype(iii).
OR
C. As definitions A or B but in 2 or 3 unrelated cases/families with the phenotype, with the addition of convincing bioinformatic or functional evidence of causation e.g. known inborn error of metabolism with mutation in orthologous gene which is known to have the relevant deficient enzymatic activity in other species; existence of an animal model which recapitulates the human phenotype.
AND
D. Evidence indicates that disease-causing mutations follow a Mendelian pattern of causation appropriate for reporting in a diagnostic setting(iv).
AND
E. No convincing evidence exists or has emerged that contradicts the role of the gene in the specified phenotype.
(i)Plausible disease-causing mutations: Recurrent de novo mutations convincingly affecting gene function. Rare, fully-penetrant mutations - relevant genotype never, or very rarely, seen in controls. (ii) Interpretable functional region: ORF in protein coding genes miRNA stem or loop. (iii) Phenotype: the rare disease category, as described in the eligibility statement. (iv) Intermediate penetrance genes should not be included.
It’s assumed that loss-of-function variants in this gene can cause the disease/phenotype unless an exception to this rule is known. We would like to collect information regarding exceptions. An example exception is the PCSK9 gene, where loss-of-function variants are not relevant for a hypercholesterolemia phenotype as they are associated with increased LDL-cholesterol uptake via LDLR (PMID: 25911073).
If a curated set of known-pathogenic variants is available for this gene-phenotype, please contact us at panelapp@genomicsengland.co.uk
We classify loss-of-function variants as those with the following Sequence Ontology (SO) terms:
Term descriptions can be found on the PanelApp homepage and Ensembl.
If you are submitting this evaluation on behalf of a clinical laboratory please indicate whether you report variants in this gene as part of your current diagnostic practice by checking the box
Standardised terms were used to represent the gene-disease mode of inheritance, and were mapped to commonly used terms from the different sources. Below each of the terms is described, along with the equivalent commonly-used terms.
A variant on one allele of this gene can cause the disease, and imprinting has not been implicated.
A variant on the paternally-inherited allele of this gene can cause the disease, if the alternate allele is imprinted (function muted).
A variant on the maternally-inherited allele of this gene can cause the disease, if the alternate allele is imprinted (function muted).
A variant on one allele of this gene can cause the disease. This is the default used for autosomal dominant mode of inheritance where no knowledge of the imprinting status of the gene required to cause the disease is known. Mapped to the following commonly used terms from different sources: autosomal dominant, dominant, AD, DOMINANT.
A variant on both alleles of this gene is required to cause the disease. Mapped to the following commonly used terms from different sources: autosomal recessive, recessive, AR, RECESSIVE.
The disease can be caused by a variant on one or both alleles of this gene. Mapped to the following commonly used terms from different sources: autosomal recessive or autosomal dominant, recessive or dominant, AR/AD, AD/AR, DOMINANT/RECESSIVE, RECESSIVE/DOMINANT.
A variant on one allele of this gene can cause the disease, however a variant on both alleles of this gene can result in a more severe form of the disease/phenotype.
A variant in this gene can cause the disease in males as they have one X-chromosome allele, whereas a variant on both X-chromosome alleles is required to cause the disease in females. Mapped to the following commonly used term from different sources: X-linked recessive.
A variant in this gene can cause the disease in males as they have one X-chromosome allele. A variant on one allele of this gene may also cause the disease in females, though the disease/phenotype may be less severe and may have a later-onset than is seen in males. X-linked inactivation and mosaicism in different tissues complicate whether a female presents with the disease, and can change over their lifetime. This term is the default setting used for X-linked genes, where it is not known definitately whether females require a variant on each allele of this gene in order to be affected. Mapped to the following commonly used terms from different sources: X-linked dominant, x-linked, X-LINKED, X-linked.
The gene is in the mitochondrial genome and variants within this can cause this disease, maternally inherited. Mapped to the following commonly used term from different sources: Mitochondrial.
Mapped to the following commonly used terms from different sources: Unknown, NA, information not provided.
For example, if the mode of inheritance is digenic, please indicate this in the comments and which other gene is involved.