Eye Disorders and Retinopathies (Eye) Panel:
This panel investigates genetic variances related to eye disorders, such as night blindness, color blindness, Retinitis pigmentosa, nystagmus, Age-related macular degeneration, cataract, glaucomas, microphthalmia, blindness, severe reduction of visual acuity, and many more.
What are Eye Disorders:
Eye disorders are medically defined as disorders that affect the retina, cornea, ophthalmic muscles as well as the optic nerves. There are hundreds of different eye diseases and vision problems. More than 3.4 million people in the U.S. age 40 and older meet the definition of “legal blindness” (visual acuity of 20/200 or less). Almost 7{788689b1f96e6e5a29b7ebdc0a74f574bcea9748ac8e484e1c92285099e82813} of U.S. children under the age of 18 have been diagnosed with an eye disease or condition. Nearly 3{788689b1f96e6e5a29b7ebdc0a74f574bcea9748ac8e484e1c92285099e82813} of children under 18 are blind or have vision impairment.
Vision loss is among the top 10 causes of disability in U.S. adults over age 18 and is one of the most common disabling conditions in children. The four most common eye conditions leading to loss of vision or blindness are cataracts, retinopathy, glaucoma, and age-related macular degeneration. However, there are hundreds of different eye diseases and disorders. Genetics play a main role in most of these conditions.
The Eye disorder next-generation sequencing (NGS) panel investigates germline variations in genes associated with these disorders, and other conditions that may present with similar phenotypes.
Method:
The test looks for inherited genetic variations (germline mutations) associated with eye disorders. Genes are instructions, written in DNA, for building protein molecules. Different people can have different versions of the same gene, with slightly different DNA sequences. Some of these variants affect health, such as those linked to dementia and retinitis pigmentosa.
Several genes are involved in eye disorders, such as macular degeneration. Age-related macular degeneration (AMD) is a problem with the retina where the macula is damaged. With AMD, patients lose central vision, while peripheral vision is often still normal. Night blindness is another genetic disorder in which vision is impaired in dim light.
Retinitis pigmentosa (RP) is a group of rare genetic eye diseases that affect the retina. RP causes cells in the retina to break down slowly over time, leading to vision loss.
Testing whether someone carries a harmful (pathogenic) variant in one of these genes can confirm whether a condition is the result of an inherited syndrome.
The Eye disorder genetic test panel investigates a panel of genes for the presence of genetic changes compared to human reference that are linked to nervous system-related conditions.
The Express Gene™ Eye Disorders and Retinopathies (Eye) Panel is a Laboratory Developed Test (LDT) validated at Express Gene Molecular Diagnostics Laboratory using Twist Exome 2.0 and Illumina NovaSeq6000 NGS Platform. This test has not been cleared or approved by the FDA.
Purpose:
This panel can help confirm a diagnosis and guide the course of treatment. Patients with eye disorders can benefit from potential gene therapies or preventive strategies. Diagnosis through genetic testing can help with the development of a management plan. The test helps physicians establish or confirm the appropriate diagnosis.
Clinical Utility:
The Eye disorder genetic testing panel can lead to more personalized treatment and symptom management, inform family members about their own risk factors, connect patients to relevant resources and support, and provide options for family planning.
Genetic Test Result Outcomes:
A. Positive Result: A pathogenic variant has been identified. Some eye disorders are dominant (one copy causes disease); others are recessive (two copies needed). Carriers may not experience symptoms but can pass the gene on.
B. Variation of Uncertain Significance (VUS): A genetic change has been found but its effect is not known. VUS results are not typically used for medical decisions. These variants may later be reclassified.
C. Negative Result: No disease-linked variant was found in the genes tested.
Limitations of Testing:
This test is designed to detect germline pathogenic variants. It does not detect:
- Repeat expansions
- Large deletions/duplications
- Copy number variations
- Structural rearrangements, inversions, translocations
- Mutations in non-coding regions
- Low-level mosaicism
- Ambiguities from pseudogenes