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Choroideremia
Choroideremia is a rare ophthalmic disorder that primarily affects ocular structures such as the retina, optic nerve, or cornea.
Prevalence
1 / 100 000
N/A
US Estimated
N/A
Europe Estimated
Age of Onset
Chidhood
ICD-10
H31.2
Inheritance Pattern
Autosomal dominant
Autosomal recessive
Mitochondrial/Multigenic
X-linked dominant
Rare
X-linked recessive
Rare View
Choroideremia is a rare genetic disorder that causes progressive vision loss due to the degeneration of the retina, retinal pigment epithelium (RPE), and choroid.
5 Facts you should know
FACT
Choroideremia is a rare X-linked recessive genetic disorder characterized by progressive degeneration of the choroid, retina, and retinal pigment epithelium, leading to vision loss
FACT
It predominantly affects males, with symptoms typically appearing in childhood or adolescence, starting with night blindness and peripheral vision loss, progressing to tunnel vision and eventual blindness
FACT
Choroideremia is caused by mutations in the CHM gene, affecting the production of a protein called Rab escort protein 1 (REP1) crucial for intracellular transport in the retina
FACT
Diagnosis involves comprehensive eye exams, including fundoscopy showing characteristic chorioretinal degeneration and genetic testing to confirm mutations in the CHM gene
FACT
Currently, no cure exists for Choroideremia, but research into gene therapies and potential treatments targeting the underlying genetic mutations is ongoing
Interest over time
Google searches
Common signs & symptoms
Night blindness (nyctalopia), often the first symptom
Progressive peripheral vision loss
Tunnel vision as disease advances
Decreased visual acuity in later stages
Eventual legal blindness, typically in adulthood
Current treatments
Supportive management includes:
- Low-vision aids
- Orientation and mobility training
- Regular ophthalmologic monitoring
Management of complications related to vision loss
References:
Allikmets R, Shroyer NF, Singh N, et al. Mutation of the retinal pigment epithelium-specific gene (CHM) in choroideremia. <i>Nat Genet.</i> 1996;14(2):232–235. doi:10.1038/ng1096-232 MacDonald IM, Russell L, Heon E, et al. Choroideremia clinical features and pathogenic variants: a comprehensive review with metaanalysis. <i>JAMA Ophthalmol.</i> 2015;133(6): 763–771. doi:10.1001/jamaophthalmol.2015.0901 Maguire AM, Simonelli F, Pierce EA, et al. Safety and efficacy of gene transfer for Leber’s congenital amaurosis. <i>N Engl J Med.</i> 2008;358(21):2240–2248. doi:10.1056/NEJMoa0802315 (gene therapy context across retinal dystrophies including early choroideremia trials) Schwartz SD, Hauswirth WW, Banin E, et al. Gene therapy for inherited retinal disease: baseline clinical characteristics of participants in trials of choroideremia gene therapy. <i>Ophthalmology.</i> 2017;124(3): 285–287. doi:10.1016/j.ophtha.2016.11.007 Sallum JM, da Silva Cunha A Jr, Kara-James N, et al. Choroideremia: review of clinical features and therapeutic approaches. <i>Ophthalmic Genet.</i> 2019;40(6): 484–495. doi:10.1080/13816810.2019.1648186