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Genetic testing for inherited retinal disease

What a test can tell you, how to get one, what it costs, and how to read the result. Written for families, and useful for the clinician who orders it.

How to get testedUnderstanding your result

Why the gene name matters

An eye exam can show that the retina is affected. Only a genetic test can show which gene is responsible, and that single fact changes what comes next.

  • It confirms the diagnosis

    Many retinal conditions look alike in the clinic, especially early. The gene result tells your doctor which one it is, and sometimes that it is a different condition than first thought.

  • It shows how the condition runs in your family

    The result reveals the inheritance pattern, which tells you who else might carry the change and whether relatives can be offered a simpler, targeted test.

  • It is the key to treatment and research

    The one gene therapy approved in the United States, for RPE65-related disease, requires a confirmed genetic result, and many clinical trials enroll only people with a known gene.

  • It keeps working after the result

    Labs reclassify variants as knowledge grows, and new trials open gene by gene. A result on file means you can be found, and re-analyzed, later.

The kinds of tests, from narrow to wide

Most people start with a gene panel. If it comes back empty, the next test reads more of the genome. Each step costs more and takes longer, and each finds some of what the last one missed.

  1. Usual first test

    Gene panel

    Reads a few hundred genes known to cause retinal disease, including some of the hidden, non-coding regions. Fast, focused, and the easiest to interpret.

    Found the cause in 55% of people in a 2024 study of 252 cases, and in 74% of those tested for the first time.

  2. If the panel is empty

    Exome

    Reads the protein-coding part of all 20,000 or so genes. Catches genes a panel leaves out and conditions that were mislabeled, at the cost of more uncertain findings.

    Adds a share of the cases a panel misses; the exact gain varies by study.

  3. If the exome is empty

    Genome

    Reads everything, including the regions between genes where some retinal-disease changes hide, and large rearrangements. The broadest and most expensive test, and the hardest to interpret.

    Costs roughly five times an exome per sample, according to a 2022 review.

How to get tested

Five steps. The order matters less than the people: a retina specialist or ophthalmologist to order it, and a genetic counselor to explain it.

  1. Ask the doctor who follows your eyes

    A retina specialist, ophthalmologist or optometrist can order the test. If yours doesn't see many inherited retinal diseases, ask for a referral to one who does, or to an academic eye center with an ocular genetics clinic.

  2. Talk with a genetic counselor first

    Pre-test counseling covers what the test can and can't show, the kinds of result you might get (including an uncertain one), how results could affect relatives, and your consent. Some programs include counseling by phone at no cost.

  3. Give the sample

    A tube of blood or a saliva kit, collected in the clinic or at home. The lab extracts DNA from it; your eyes are not involved.

  4. The lab reads and classifies

    The lab sequences the genes on the test and sorts every difference it finds into one of five classes using guidelines from the American College of Medical Genetics and Genomics, from clearly disease-causing to clearly harmless.

  5. Get the result with a counselor

    The report goes back to the clinician who ordered it. Ask to go through it with a genetic counselor so the classification, the inheritance pattern and the next steps are clear before you leave.

Reading the result

Every change the lab finds is placed on a five-point scale. The scale is about evidence, not severity: it says how sure the lab is that a change causes disease.

  1. Benign

    Not the cause

    Strong evidence that this is a normal variation seen in healthy people.

  2. Likely benign

    Probably not the cause

    Evidence points away from disease, but with less certainty.

  3. Uncertain significance (VUS)

    Not enough evidence either way

    Common, especially in less-studied genes and populations. A VUS may be reclassified as evidence accumulates, in either direction.

  4. Likely pathogenic

    Probably the cause

    Strong evidence for disease, short of definitive.

  5. Pathogenic

    The cause

    Well-established evidence that this change causes the condition.

Classes follow the 2015 ACMG/AMP standards used by clinical laboratories.

Words you'll see on the report

Heterozygous
One copy of the gene carries the change. Enough to cause disease in dominant conditions; carrier status in recessive ones.
Homozygous
Both copies carry the same change.
Compound heterozygous
Two different changes in the same gene, one from each parent. The usual finding in recessive retinal disease.
Hemizygous
A change on the X chromosome in a male, who has one X. Seen in X-linked conditions.
De novo
A new change not inherited from either parent.
Carrier
Someone with one copy of a recessive change and no symptoms.

If nothing is found

A negative panel does not rule out a genetic cause. In the studies above, a third or more of people tested were left without an answer after a panel. The usual next steps are a broader test (exome or genome), periodic re-analysis of the data as new genes are described, and research studies that take unsolved cases. Ask your counselor which applies to you.

After the result

Four things a result makes possible.

  • Go over it with a genetic counselor

    Inheritance, what it means for children and siblings, reproductive options, and a plan for re-checking an uncertain result.

    Find genetic counseling

  • Search trials for your gene

    Our trial search is live from ClinicalTrials.gov and can be filtered by gene. Bring what you find to your specialist.

    Search active trials

  • Offer relatives a targeted test

    Once the family variant is known, blood relatives can be tested for that one change.

  • Join a registry

    The Foundation Fighting Blindness My Retina Tracker Registry lets researchers and trial sponsors find people with your gene.

    About the registry (opens in a new tab)

Medical Disclaimer

This information is for educational purposes only and does not constitute medical advice. It is not a substitute for seeking medical opinions, nor an endorsement of any treatments, research, or organizations. Trial information is sourced from ClinicalTrials.gov and public press releases. Genetic testing and clinical management should be performed by qualified healthcare professionals, including ophthalmologists and genetic counselors.

Sources

  1. American Academy of Ophthalmology, Clinical Assessment of Patients with Inherited Retinal Degenerations (consensus statement, 2022).
  2. Mustafi D, et al. The current state of genetic testing platforms for inherited retinal diseases. Ophthalmology Retina, 2022.
  3. Genetic analysis of 252 index cases with inherited retinal diseases using a panel of 351 retinal genes. Genes, 2024.
  4. Richards S, et al. Standards and guidelines for the interpretation of sequence variants (ACMG/AMP), Genetics in Medicine, 2015.
  5. Foundation Fighting Blindness, My Retina Tracker Genetic Testing Program (program page, materials dated December 2025).
  6. Invitae Unlock Inherited Retinal Disease program (Labcorp program page).
  7. National Human Genome Research Institute, Genetic Discrimination (GINA).
  8. Blueprint Genetics, Retinal Dystrophy Panel (test page, 2026).