Eye diseases can occur from both genetic and nongenetic (environmental) factors. If you have a family member who has a genetic eye disease, you may be at greater risk of developing the disease as well. Your doctor may recommend genetic testing. Experts at The Ohio State University Wexner Medical Center’s Departments of Ophthalmology and Genomic Medicine use genetic testing and genomic sequencing to determine your risk of developing genetic eye diseases.

What are genetics and genomics?

Genetics determine what traits you inherit from your parents, including genes that can increase your risk of developing certain diseases. Your genes control the traits that make you who you are. From the color of your eyes, to your sleep patterns, to your overall health, your genes are at play.

Your genomic sequence is comprised of chains of genes. Certain genes and variations in genomic sequences can increase your risk of developing specific diseases. Genomics is the field of medicine that considers your entire genome sequence, as well as how environmental factors affect your health, to assess why you may develop a condition or disease and how you will respond to treatment.

Genetic testing and genomic sequencing are a form of precision medicine. Precision medicine empowers you and your doctor to know your particular risk of developing certain diseases. Your care team uses this information to tailor your healthcare and treatment specifically for you.

How is genetic testing done?

Genetic testing is performed by collecting a blood or saliva sample and sending it to a lab to examine your genes, which are made up of DNA. Genetic testing shows which genes you have and if there are any variations, deletions or multiplications of those genes or chains of genes. The lab sends your results to your doctor or a genetic counselor.

What is ophthalmic genetic counseling?

A genetic counselor is a health care professional who has graduate education and training in genetics and counseling. A genetic counselor reviews your family history, results of genetic testing and genomic sequencing. They use this information to help you understand your risk for inheriting certain diseases, as well as available treatment options.

The Ohio State Wexner Medical Center offers ophthalmic genetic counseling with licensed genetic counselors who focus on risk and treatment of genetic eye diseases. Genetic counselors at the Ohio State Wexner Medical Center can help explain what your family history and genetic testing results mean and connect you with doctors and resources to help you create the best possible care plan.

Genetic eye diseases

There are 200-300 genes that are known to cause eye diseases that doctors can screen for. Some genetic eye diseases that are commonly screened for include:

• Corneal dystrophies – The cornea is the clear, outer layer of the eye that helps focus light so you can see clearly. Corneal dystrophies consist of a group of eye disorders in which abnormal material builds up in the cornea and obstructs vision. Corneal dystrophies usually affect both eyes.
• Retinal dystrophies – The retina is a thin layer of tissue located on the inside wall at the back of the eye. The retina is responsible for sensing light and transmitting signals to the brain to create visual perception. Retinal dystrophies consist of a group of eye disorders that damage cells within the retina and lead to vision loss.
• Keratoconus – Keratoconus occurs when your cornea thins and protrudes outward, causing blurred vision. It’s suspected that both genetic and environmental factors can contribute to keratoconus, with the genetic component affecting the structure of collagen that can lead to a weak cornea.
• Glaucoma – People with glaucoma have vision loss due to increased pressure within the eye. Increased pressure within the eye has been linked to the presence of certain genes.

Who should have ophthalmic disease risk assessment?

Ophthalmic disease risk assessment is the process of completing genetic testing and having a genetic counselor or doctor review your results along with your genomic sequence and family history. They use this information to determine if you, and even your family members, are at increased risk of developing a genetic eye disease.

You should have ophthalmic disease risk assessment if:

• You have a parent or sibling who has a diagnosed genetic eye disease
• You have a diagnosed eye disease that could have a genetic factor

The Ohio State Wexner Medical Center is committed to maintaining your eye health and protecting your vision. Identifying your risk of developing a genetic eye disease allows you to be proactive in your health care, for your doctors to closely monitor you and for greater opportunity to preserve your vision by detecting a genetic eye disease early.

What is the role of research in eye genetics?

Genomic and precision medicine are the future of health care. Genetic testing and genomic sequencing can reveal increased risk of developing certain diseases and allow doctors to be more proactive and less reactive. Scientists and medical researchers at the Ohio State Wexner Medical Center study genomic sequences and environmental factors to help identify gene variations and external factors responsible for inherited eye diseases and other conditions that can run in families. These can range from bleeding and blot-clotting disorders to diseases of the skin, kidney and lung.

Trends can be identified when many people with the same genetic variations have the same disease. The Ohio State Wexner Medical Center uses lab results and data from patients who participate in the Eye Genetics Program to discover new trends in genetic variations and links to diseases. Pinpointing genetic causes of different diseases can improve diagnosis, treatment and outcomes for patients and their families.

What to expect with ophthalmic risk assessment at Ohio State

If your doctor has recommended you have genetic testing done, or if you have a family member who has a genetic eye disease diagnosis and you wish to have an ophthalmic risk assessment, you can expect the following steps:

• Check if your insurance covers genetic testing. Contact your insurance company to ask if genetic testing and genetic counseling are covered under your plan. One of the most common questions patients have is “Will my insurance cover genetic counseling?” The ophthalmology social worker can help you find out if your insurance covers genetic testing and genetic counseling.
• See your ophthalmologist or optometrist. If you haven’t seen an optometrist or ophthalmologist within the past year, you need to schedule an appointment. You should have a vision work-up completed within one year of going for genetic testing. Your ophthalmologist or optometrist will refer you to a genetic counselor at the Ohio State Wexner Medical Center and also enter an order for genetic testing.
• Get tested. You will go to an Ohio State Wexner Medical Center lab to have a blood or saliva sample collected by a lab technician. Your sample will be screened in a lab for your genes and genomic sequence.
• Lab results will be sent to a genetic counselor. The lab will send your results to a genetic counselor at the Ohio State Wexner Medical Center who will review and verify the results.
• Meet with a genetic counselor. You will meet with a genetic counselor who will discuss your results with you. The genetic counselor will address what your results mean for you. They may recommend your family members have genetic testing done as well.
• Meet with your doctor. Your genetic counselor will refer you back to your ophthalmologist or optometrist who will recommend a prevention or monitoring plan, if needed. Since some genetic variations or diseases affect multiple systems in the body, your genetic counselor may refer you to multiple specialists who can provide you with an individualized treatment plan.