Types of Genetic Eye and Vision Disorders
Genetic disorders can impact every part of our bodies and bodily functions, including vision. If you have a personal or family history of vision loss, blindness, or other eye and vision problems and your doctors can’t figure out the underlying cause, it may be time to look to genetics. Symptoms related to your vision may occur on their own or alongside other health issues. Either way, clinical geneticists can help diagnose and manage patients who are having difficulties with their vision due to a genetic condition.
Examples of Inherited Eye and Vision Disorders
Let’s look at a few types of inherited eye and vision disorders.
1. Orbital Dysmorphology: The bones around the eye are called the orbit. Orbital dysmorphology refers to the unusual development of these bones. These abnormalities can affect the shape, size, or structure of the eye socket. In turn, this condition can cause the eyes to be misaligned or not function properly.
2. Corneal Involvement: The cornea is the clear, dome-shaped surface at the front of the eye. Corneal involvement means there’s a problem with the cornea. It can cause issues like cloudiness, scarring, or thinning. Patients with these conditions may experience blurry vision, eye pain, or light sensitivity. In some cases, treatments like corneal cross-linking, contact lenses, or corneal transplants can help to restore vision. New technologies, like artificial corneas, are also being developed.
3. Lens Involvement: The lens is the part of the eye that helps focus light onto the retina. If there’s a problem with the lens, like cataracts (clouding of the lens) or improper shape, individuals may have blurry vision or difficulty focusing on objects at different distances. Lens dislocation (when the lens moves out of its normal position) is an example of a lens involvement that can occur with some connective tissue disorders.
4. Iris Involvement: The iris is the colored part of the eye that controls how much light enters. Problems with the iris can include abnormal development or holes (coloboma). These conditions can affect how well your eye adjusts to light and may cause issues like glare or sensitivity to bright lights.
5. Retinal Involvement: The retina is the layer at the back of the eye that senses light and sends visual information to the brain. Retinal involvement refers to inherited conditions that affect the retina, such as retinitis pigmentosa, which can lead to vision loss, particularly at night or in low-light conditions, and can eventually lead to blindness.
Doctors can manage some retinal conditions with low-vision aids, vitamin supplements, and retinal implants. Gene therapies that target the underlying genetic defect have also shown promise in restoring some vision.
6. Optic Nerve Involvement: The optic nerve carries visual information from the eye to the brain. Problems with the optic nerve, such as optic nerve atrophy or glaucoma, can interfere with this process. Optic nerve issues can lead to partial or total vision loss.
For optic nerve issues, especially glaucoma, eye drops, surgery, and medication may slow progression but cannot restore lost vision. Research in gene therapy and regenerative medicine (such as stem cells) aims to develop solutions that protect or regenerate the optic nerve.
7. Oculomotor Involvement: Oculomotor refers to the muscles that control eye movement. If these muscles or the nerves that control them don’t work properly, it can result in eye misalignment (crossed eyes), difficulty moving the eyes, or double vision. Vision therapy, glasses, or surgery may help to manage these symptoms.
8. Cortical Blindness: Cortical blindness occurs due to damage in the brain’s visual processing areas, rather than in the eyes themselves. While the eyes may work properly, the brain can’t interpret the signals, resulting in partial or complete blindness. Treatment for cortical blindness focuses on managing symptoms, including helping people improve their visual perception and make the most out of their remaining eyesight.
9. Refractive Errors: Refractive errors happen when the shape of the eye prevents light from focusing correctly on the retina. Common types include nearsightedness (myopia), farsightedness (hyperopia), and astigmatism (irregular curvature of the eye’s surface), which can usually be corrected with glasses or contact lenses. For most people, refractive errors are not associated with a genetic condition. However, certain genetic syndromes can cause vision issues like nearsightedness or farsightedness.
Managing and Treating Genetic Vision Disorders
Once a doctor diagnoses your genetic eye condition, your providers can create a more personalized and effective care plan. They can potentially slow the disorder’s progression, and, in some cases, treat the condition and alleviate symptoms.
Whether a vision disorder can be treated depends on its cause, severity, and which part of the eye or visual system is affected. For example, patients with lens or corneal issues may have opportunities to receive a transplant or artificial replacement. With many conditions, medical advances like these have already or will soon open up new possibilities!
At SequenceMD, we specialize in the diagnosis, treatment, and management of patients with rare and inherited genetic disorders. Our genetics clinical team works closely with doctors from all specialties. We consult with providers on challenging clinical cases, suspected genetic disorders, and patients with established genetic diagnoses. Contact us today for more information or to talk with us about a genetic evaluation.
