Causes
There are at least 27 genes that are mutated in Leber Congenital Amaurosis (LCA), a genetic disorder. For the retina, the light-sensitive tissue back of the eye, to develop and function properly, these genes are crucial. To develop LCA, an individual must inherit two copies of the mutated gene, one from each parent. LCA is inherited in an autosomal recessive manner.
Symptoms
Children with LCA often experience the following symptoms in infancy or early childhood:
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Affected infants may not respond to light due to severe vision impairment or blindness.
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Eye movements that are rapid and involuntary are known as nystagmus.
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Light sensitivity is called photophobia.
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Pupillary Reflex: Reduced or absent reaction to light by the pupils.
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Franceschetti's oculo-digital sign, where children poke or press their eyes.
Diagnosis
Clinical evaluations and genetic testing are used to diagnose LCA:
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An ophthalmologic examination measures the electrical response of the retina to light using tools like electroretinography (ERG).
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Through blood tests, mutations in the genes associated with LCA can be detected.
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A family history of vision problems and genetic conditions should be evaluated.
Treatment
LCA is currently incurable, but treatment focuses on managing symptoms and improving quality of life:
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The FDA has approved Luxturna, a gene therapy that treats LCA caused by mutations in the RPE65 gene, for certain types of LCA.
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A low vision aid is a device that helps maximize remaining vision by using magnifiers, specialized glasses, and other tools.
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Children with vision impairments can receive orientation and mobility training as well as educational support.
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Under medical supervision, vitamin A supplementation may help slow the progression of the disease in some cases.
Prevention
Understanding and managing genetic risks are essential to preventing LCA:
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A genetic counselor can help prospective parents understand their risks of having a child with LCA if their family has a history of it.
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In some cases, prenatal genetic testing can identify whether a fetus has LCA-associated genes.
Conclusion
It is a severe genetic disorder that causes early-onset vision impairment or blindness. There are mutations in various retinal genes that cause this condition. The symptoms typically manifest in infancy and include severe vision impairment, nystagmus, and photophobia. Genetic testing and ophthalmological examinations are used to diagnose it. Gene therapy, low vision aids, and supportive services can help manage symptoms and improve quality of life. Genetic counseling and prenatal testing are important preventive measures for families at risk.
