As a result of degeneration of the choroid, retina, and retinal pigment epithelium, Choroideremia causes progressive vision loss. In this article, we'll discuss the causes, symptoms, diagnosis, treatment, and prevention of this condition.
Causes
As a result of mutations in the CHM gene, choroideremia is caused by the breakdown of a protein known as Rab escort protein 1 (REP1). The protein transports and functions other proteins within the retina and choroid. As a result of mutations in the CHM gene, REP1 is disrupted, leading to the degeneration of the retina and choroid.
Symptoms
Choroideremia typically manifests in childhood or early adulthood and gradually worsens over time. Common symptoms include:
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The first sign of the disease is often night blindness
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Loss of peripheral vision (tunnel vision) over time
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Decreased central vision
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Perception of color is difficult
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Light sensitivity (photophobia)
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In advanced stages of the disease, vision loss can lead to legal blindness
Diagnosis
Choroideremia is diagnosed through a comprehensive eye examination by an ophthalmologist or optometrist. Diagnostic tests may include:
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Testing of visual acuity: to assess central vision
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Testing the peripheral vision with a visual field test
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A fundoscopy is used to examine the retina and choroid for signs of choroideremia, such as chorioretinal atrophy (thinning of the retina and choroid).
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Identifying mutations in the CHM gene that confirm the diagnosis of choroideremia through genetic testing
Treatment
There is no cure for choroideremia, and treatment aims to manage symptoms and slow disease progression.
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The use of low-vision aids such as magnifying glasses, telescopes, and electronic magnifiers can help individuals with choroideremia maintain their independence and maximize their remaining vision.
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Experimental gene therapy approaches are being investigated as potential treatments for choroideremia, designed to replace the faulty CHM gene with a functional copy to slow or halt vision loss progression.
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Detecting and managing complications associated with choroideremia, such as cataracts and retinal detachments, requires regular eye examinations and monitoring.
Prevention
There are no known ways to prevent the development of choroideremia, since it is a genetic disorder caused by mutations in the CHM gene. In order to understand their risk of passing the condition on to their children, individuals with a family history of choroideremia may benefit from genetic counseling. For individuals with choroideremia, early diagnosis and management of symptoms can improve outcomes and quality of life.
As a result of degeneration of the retina and choroid in the eye, choroideremia is a rare genetic condition characterized by progressive vision loss. Despite the fact that there is no cure for the condition, early diagnosis and management of symptoms are crucial to maximizing remaining vision and maintaining quality of life. Symptoms of choroideremia, such as night blindness or peripheral vision loss, should be evaluated and treated by an eye care professional.
