crumbs cell polarity complex component 1
Last updated 6 Oct 2022
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The CRB1 gene provides instructions for making a protein that plays an essential role in normal vision. This protein is found in the brain and the retina, which is the specialized tissue at the back of the eye that detects light and colour.
Normal function
The CRB1 gene provides instructions for making a protein that plays an essential role in normal vision. This protein is found in the brain and the retina, which is the specialized tissue at the back of the eye that detects light and colour.
In the retina, the CRB1 protein appears to be critical for the normal development of light-sensing cells called photoreceptors. Studies suggest that this protein is part of a group (complex) of proteins that help determine the structure and orientation of photoreceptors. The CRB1 protein may also be involved in forming connections between different types of cells in the retina.
Conditions referring to this gene or chromosome
Other names
CRUM1_HUMAN
crumbs family member 1, photoreceptor morphogenesis associated
crumbs homolog 1
crumbs homolog 1 (Drosophila)
LCA8
RP12
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Further reading and references
- crumbs cell polarity complex component 1; MedlinePlus, National Library of Medicine.
- Antropoli A, Arrigo A, Pili L, Bianco L, Berni A, Saladino A, Bandello F, Battaglia Parodi M. Pigmented paravenous chorioretinal atrophy: Updated scenario. Eur J Ophthalmol. 2024 Jul;34(4):941-951. doi: 10.1177/11206721231199118. Epub 2023 Sep 5.
- Daich Varela M, Georgiou M, Alswaiti Y, Kabbani J, Fujinami K, Fujinami-Yokokawa Y, Khoda S, Mahroo OA, Robson AG, Webster AR, AlTalbishi A, Michaelides M. CRB1-Associated Retinal Dystrophies: Genetics, Clinical Characteristics, and Natural History. Am J Ophthalmol. 2023 Feb;246:107-121. doi: 10.1016/j.ajo.2022.09.002. Epub 2022 Sep 12.
- den Hollander AI, Davis J, van der Velde-Visser SD, Zonneveld MN, Pierrottet CO, Koenekoop RK, Kellner U, van den Born LI, Heckenlively JR, Hoyng CB, Handford PA, Roepman R, Cremers FP. CRB1 mutation spectrum in inherited retinal dystrophies. Hum Mutat. 2004 Nov;24(5):355-69. doi: 10.1002/humu.20093.
- den Hollander AI, Heckenlively JR, van den Born LI, de Kok YJ, van der Velde-Visser SD, Kellner U, Jurklies B, van Schooneveld MJ, Blankenagel A, Rohrschneider K, Wissinger B, Cruysberg JR, Deutman AF, Brunner HG, Apfelstedt-Sylla E, Hoyng CB, Cremers FP. Leber congenital amaurosis and retinitis pigmentosa with Coats-like exudative vasculopathy are associated with mutations in the crumbs homologue 1 (CRB1) gene. Am J Hum Genet. 2001 Jul;69(1):198-203. doi: 10.1086/321263. Epub 2001 May 24.
- den Hollander AI, Roepman R, Koenekoop RK, Cremers FP. Leber congenital amaurosis: genes, proteins and disease mechanisms. Prog Retin Eye Res. 2008 Jul;27(4):391-419. doi: 10.1016/j.preteyeres.2008.05.003. Epub 2008 Jun 1.
- den Hollander AI, ten Brink JB, de Kok YJ, van Soest S, van den Born LI, van Driel MA, van de Pol DJ, Payne AM, Bhattacharya SS, Kellner U, Hoyng CB, Westerveld A, Brunner HG, Bleeker-Wagemakers EM, Deutman AF, Heckenlively JR, Cremers FP, Bergen AA. Mutations in a human homologue of Drosophila crumbs cause retinitis pigmentosa (RP12). Nat Genet. 1999 Oct;23(2):217-21. doi: 10.1038/13848.
- Gosens I, den Hollander AI, Cremers FP, Roepman R. Composition and function of the Crumbs protein complex in the mammalian retina. Exp Eye Res. 2008 May;86(5):713-26. doi: 10.1016/j.exer.2008.02.005. Epub 2008 Feb 26.
- Jacobson SG, Cideciyan AV, Aleman TS, Pianta MJ, Sumaroka A, Schwartz SB, Smilko EE, Milam AH, Sheffield VC, Stone EM. Crumbs homolog 1 (CRB1) mutations result in a thick human retina with abnormal lamination. Hum Mol Genet. 2003 May 1;12(9):1073-8. doi: 10.1093/hmg/ddg117.
- Kumaran N, Pennesi ME, Yang P, Trzupek KM, Michaelides M. Nonsyndromic Leber Congenital Amaurosis / Early-Onset Severe Retinal Dystrophy Overview. 2018 Oct 4 [updated 2025 Dec 4]. In: Adam MP, Bick S, Mirzaa GM, Wallace SE, Amemiya A, editors. GeneReviews(R) [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2026. Available from http://www.ncbi.nlm.nih.gov/books/NBK531510/
- Lotery AJ, Jacobson SG, Fishman GA, Weleber RG, Fulton AB, Namperumalsamy P, Heon E, Levin AV, Grover S, Rosenow JR, Kopp KK, Sheffield VC, Stone EM. Mutations in the CRB1 gene cause Leber congenital amaurosis. Arch Ophthalmol. 2001 Mar;119(3):415-20. doi: 10.1001/archopht.119.3.415.
- Richard M, Roepman R, Aartsen WM, van Rossum AG, den Hollander AI, Knust E, Wijnholds J, Cremers FP. Towards understanding CRUMBS function in retinal dystrophies. Hum Mol Genet. 2006 Oct 15;15 Spec No 2:R235-43. doi: 10.1093/hmg/ddl195.
- Saberi M, Golchehre Z, Karamzade A, Entezam M, Eshaghkhani Y, Alavinejad E, Khojasteh Jafari H, Keramatipour M. CRB1-Related Leber Congenital Amaurosis: Reporting Novel Pathogenic Variants and a Brief Review on Mutations Spectrum. Iran Biomed J. 2019 Sep;23(5):362-8. doi: 10.29252/.23.5.362. Epub 2019 May 19.
- van de Pavert SA, Kantardzhieva A, Malysheva A, Meuleman J, Versteeg I, Levelt C, Klooster J, Geiger S, Seeliger MW, Rashbass P, Le Bivic A, Wijnholds J. Crumbs homologue 1 is required for maintenance of photoreceptor cell polarization and adhesion during light exposure. J Cell Sci. 2004 Aug 15;117(Pt 18):4169-77. doi: 10.1242/jcs.01301.
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