The term “genetic eye diseases” refers to conditions that are caused by a mutation in the DNA of an individual, rather than by an infection or injury.
Although these conditions affect vision, they are rarely life-threatening (though you should always consult a doctor for proper diagnosis). In some cases, genetic eye diseases cause both eyes to be affected; in others, only one eye is affected.
Studies show there are approximately 6,000 known genetic disorders caused by one or more mutations in DNA, as reported by John Hopkins Medicine.
Depending on the disease, some people may experience mild vision loss, while others could go completely blind. Regardless of the severity of symptoms, it’s important to know what steps you can take to prevent further damage if you have genetic eye disease.
Genetic eye diseases can cause a wide range of conditions that affect your eyesight. If you notice changes in your vision, it’s important to talk to a doctor.
5 Common Types of Genetic Eye Conditions
Asking questions and knowing the facts about genetic eye diseases can help you get the treatment you need and prevent vision loss. The five most common genetic eye conditions include:
Age-Related Macular Degeneration (AMD)
AMD is an eye disease that affects an individual’s central vision. This happens when the macula (the part of the eye that controls sharp, straight-ahead vision) starts to deteriorate due to aging. Macular degeneration is categorized as the leading cause of age-related vision loss in people over 50.
The symptoms of age-related macular degeneration depend on the stage and type of AMD, but since it’s a progressive disease, symptoms usually get worse over time. Early symptoms of AMD can include distorted vision or blind spots that appear and disappear over time.
Effects of macular degeneration
There are two types of AMD; dry AMD and wet AMD and the disease progresses in three stages: early, intermediate, and late.
Dry AMD may develop without symptoms. In intermediate stages, some people notice mild blurriness in their vision or trouble seeing in low lighting.
In late-stage dry (or wet) AMD, vision distortion increases, in which straight lines look wavy or crooked. As the disease progresses, individuals may witness a blurry area near the center of their vision grow larger as the condition advances. Colors may also appear duller than before, making it difficult to see clearly in low lighting.
Glaucoma is a group of diseases that damage optic nerve fibers, which are responsible for carrying visual information from the retina to the brain.
It is the leading cause of blindness in adults over sixty-five years old and is characterized by increased pressure within the eyeball that damages the optic nerve that transmits information from your eye to the brain.
Effects of glaucoma
Without treatment, glaucoma can cause blindness by damaging parts of the eye that control vision and by making it harder for fluid to drain from the eye.
Glaucoma has no early symptoms, so regular eye exams are essential for detecting it early on.
Retinitis pigmentosa (RP) is a group of rare genetic disorders that occur due to harmful changes in any one of more than 50 genes.
Genes carry the instructions for producing proteins needed in cells within the retina, called photoreceptors. Three types of gene mutations lead to damage in photoreceptors; inability to produce a required protein, production of a toxic protein, and production of an abnormal protein.
Photoreceptors are cells present within the retina that convert light into signals that are sent to the brain. There are two types of photoreceptor cells: rods and cons, that enable our night vision and color vision, respectively.
Effects of retinitis pigmentosa
During the early stages of RP, rods that are responsible for scotopic vision are damaged more in comparison to cones. Due to the damaged rods people with retinitis pigmentosa experience night blindness and a reduced visual field.
In the later stages the loss of cones responsible for photopic vision causes people to develop tunnel vision and makes it difficult to recognize faces and objects.
Other symptoms include loss of side (peripheral) vision.
Cataracts form when proteins clump together and start to cloud your lens, causing it to become foggy or opaque. This can lead to impaired vision and blindness if left untreated. Common symptoms include seeing halos around lights at night, blurry vision with colors appearing faded, or double-vision.
Cataracts are most common in older people and may be inherited from parents who have a history of cataracts themselves.
Surgery is possible for cataracts using lasers or other techniques to break down the protein deposits in your lens so that you can again see clearly without glasses or contacts.
As the name suggests, this eye condition is directly connected with diabetes. When the blood sugar levels present in the body begin to increase, this causes damage to the blood vessels in the retina.
The retina is connected to a network of tiny blood vessels that ensure a constant supply of blood.
Any abnormalities or changes in these blood vessels can cause low vision or loss of vision. These changes include swelling or leaking of blood vessels, or stopping blood from passing through or due to new abnormal blood vessels growing on the retina.
Effects of diabetic retinopathy
It’s difficult to notice any symptoms of diabetic retinopathy in the early stages; however, routine eye examinations and early detection of any early signs of the condition can be picked up during diabetic eye screening.
Some of the common symptoms of diabetic retinopathy are seeing shapes or floaters in your field of vision, blurred vision, difficulty seeing in the dark, etc.
The most basic way to prevent the disease from getting worse is by controlling blood sugar and cholesterol levels and getting medical advice quickly if you notice any changes in your vision.
Many eye diseases, such as glaucoma and age-related macular degeneration, have no symptoms in the early stages, which is why early treatment is important before these conditions become serious.
There may be no cure for genetic eye conditions, but there are treatments to help you cope with and even minimize the effects of these diseases. In most cases, early detection and intervention can have a positive impact on your vision.
Early diagnosis means early treatment, and early treatment means a better long-term prognosis for patients with retinitis pigmentosa and macular degeneration (the two leading causes of blindness in children).
Treatment options vary depending on the underlying condition and how severe it is. Genetic eye conditions that cause symptoms and vision loss may be treated with surgical procedures, medications, or other therapies to improve your vision and reduce symptoms. Genetic eye conditions that don’t cause symptoms may only need monitoring by an ophthalmologist to ensure there are no other problems.