Is Bad Eyesight Genetic (and Can You Do Something About It)?

Is poor vision genetic?

The simple answer to this age-old debate is yes! Poor eyesight is largely attributed to genetics.

According tothe World Health Organization, at least 2.2 billion people in the world suffer from some vision impairment. The most frequent eye conditions are myopia (nearsightedness), hyperopia (farsightedness), and astigmatism, which are inherited refractive disorders that are also affected by lifestyle and environment.

The natural follow-up question is: if bad eyesight is genetic, can lifestyle modification improve it? The good news is that even if you are genetically predisposed to vision issues, there are a few things you can do to keep your eyes safe and healthy.

Let us explore the reason behind poor vision, define poor eyesight and discuss how nature and nurture affect the eyes.

What Does “Bad Eyesight” Actually Mean

Depending on the discipline, bad eyesight is understood in different ways. To have an in-depth understanding of bad eyesight and correct misinterpretation of symptoms, we will look at bad eyesight from different perspectives.

Biochemically, bad eyesight can be defined as a molecular or cellular dysfunction in the eyes. The molecular mechanism behind vision impairment highlights how abnormalities in proteins and enzymes can affect sight. These proteins, enzymes and pigments like rhodopsin are essential for light detection and signal interpretation.

From an anatomical point of view, bad eyesight means a structural anomaly or damage to the physical parts of the eye. The major focus is on damage or dysfunction in the shape, size or structure of eye parts like the cornea, lens, retina and optic nerve.

In physiology, we define bad eyesight as a functional failure in the process of seeing. In this case, the eye structures may remain intact, but the eye part just doesn’t function properly. An example of this is seen in amblyopia, also known as lazy eyes; the eye may appear normal, but doesn’t function well due to poor brain-eye coordination.

Clinically, bad eyesight is simply defined as visual acuity less than 6/6 or 20/20 when uncorrected. Visual acuity measures how well you see details at a distance, but it doesn’t necessarily mean that you have good eyesight. Visual acuity indicates the sharpness or clarity of vision at a distance of 20 feet. For instance, if you have a visual acuity of 40/100, it simply means that you need to be as close as 40 feet to see what a person with normal vision can see at 100 feet.

The Influence of Genetics on Eye Development

Research has shown that genetic factors play a major role in the disorder of the eyes and the progression of hereditary eye diseases. This evidence has grown over the past 25 years, giving insight into ocular diseases.

The result of this knowledge growth is an accurate mapping of genes and their variants that can influence the vision and health of our eyes. For example, knowing the family history of vision problems is crucial for developing treatment plans or early follow-up care to avoid vision complications later.

Let us look at how genetics influences eye development:

• Eye Size and Shape: Genetics determines the length and curvature of the eye, which affects refractive errors like myopia and hyperopia.
• Retina and Photoreceptors: Genes regulate the development of rods and cones; mutations can lead to inherited conditions like retinitis pigmentosa, colour blindness, and Leber congenital amaurosis.
• Lens Clarity: Genetic defects can cause congenital cataracts or early clouding of the lens.
• Optic Nerve Formation: Genetic abnormalities may disrupt optic nerve development, increasing the risk of glaucoma or optic nerve hypoplasia.
• Hereditary Eye Conditions: Conditions like strabismus, amblyopia, keratoconus, and age-related macular degeneration often run in families.

Based on this information, it has become evident that mutations or inherited traits can influence eye size, clarity, coordination, and overall vision quality. While environmental factors and lifestyle also play roles, family history is one of the strongest indicators of genetic predisposition to future eye conditions.

Common Hereditary Vision Issues: Myopia, Hyperopia, Astigmatism

Three common hereditary vision issues are myopia, hyperopia and astigmatism, all of which are refractive errors and often influenced by genetics. The World Health Organization defines refractive errors as a very common eye condition that occurs due to an abnormal shape or length of the eye. People with refractive errors experience blurred vision because the light doesn’t focus correctly on the retina.

Here are the main things to know about the three most common hereditary vision issues:

• Myopia: also known as nearsightedness, and affects nearly 42% of the U.S. population, is described as the inability to see far objects clearly. It happens when the cornea is too long or too curved, causing light to focus in front of the retina instead of directly on it.

• Hyperopia: Hyperopia affects roughly 14 million people (10%) in the U.S. It is also known as farsightedness and is characterized by the ability to see far objects, but near objects appear blurry. This happens because the cornea is either too flat or the eye is too short, so the light focuses behind the retina, not directly on it.

• Astigmatism: According to the American Academy of Ophthalmology, the prevalence of astigmatism is approximately 33% of the population. However, some estimates range from 10% to over 60%, depending on age and measurement methods. Astigmatism in individuals means that vision is blurry or distorted at all distances due to an irregularly shaped cornea or lens. The cornea or lens is football-shaped instead of basketball-shaped, allowing light to focus on different points on the cornea.

All refractive errors are genetically influenced errors that affect how light focuses on the eye. While environmental and lifestyle factors like reading habits and screen use may influence their development, the occurrence is strongly traced to family history.

Genetics Links to Serious Eye Conditions: Glaucoma, Macular Degeneration

On a scale of severity, some eye conditions take the cake. These conditions are considered serious because they silently rob individuals of their sight before they realize anything is wrong. Unlike common conditions like cataracts, glaucoma, and macular degeneration have no cure and treatment only slows progression.

Let’s study the genetic link to these conditions:

• Glaucoma: According to the Centers for Disease Control and Prevention, close to 4.2 million Americans currently live with glaucoma, (1.5 million with vision‑affecting disease) and it is the leading cause of blindness around the world. Glaucoma affects all age groups, and yes, it is genetically linked. Your risk of developing glaucoma can increase by up to six times if there is a positive family history of the condition. Glaucoma’s genetic basis, however, is complicated and deviates from the standard Mendelian Inheritance rule.

• Macular Degeneration: The disease known as macular degeneration, or age-related macular degeneration (AMD), is more common in people aged 55 and older. It affects the retina, which is the part of the eye that receives light. Researchers have identified over 30 genes that are linked to AMD. Having an AMD gene increases your risk of developing the disease, but it does not guarantee it.

By understanding your genetic risk for conditions like glaucoma and AMD, you can take proactive steps to protect your vision. The first step to understanding your risk is taking the appropriate eye exams and lifestyle adjustments.

Nature vs. Nurture: Environment and Lifestyle Impact on Genes

The nature vs nurture debate explores the extent to which genes (nature) and our environment/lifestyle (nurture) impact disease conditions, and where the two of them interact.

The two concepts were formally viewed as independent of each other, but studies have shown that all animal behaviours are a result of both genes and environmental factors.

Nature (genes) 

This refers to the traits you inherited directly from your parents, they are:

• Height
• Eye color
• Susceptibility to certain diseases
• Personality tendencies
• Blood type

These characteristics/features are written in your DNA.

Nurture (environment/lifestyle) 

This includes everything outside your genes that shapes who you are.

They are:

• Diet and nutrition
• Your upbringing and education
• Physical activities
• Where you live
• Social relationship
• Exposure to stress or trauma

These environmental/lifestyle factors, though not in your genetic makeup, can greatly influence how your genes express themselves. For example, a person might have a genetic risk for glaucoma, but a healthy lifestyle and diet can slow those genes from being expressed. This is where nature and nurture meet.

Do You Inherit Vision Problems From One Parent? 

Yes, but it depends! Let’s explain.

Autosomal dominant inheritance refers to conditions or vision issues that can be inherited from a single parent. In contrast, autosomal recessive inheritance requires that both parents carry and pass on the faulty gene for the condition to manifest in the child.

Some vision issues associated with autosomal dominant inheritance include:

• Retinitis pigmentosa (about 15–25 % of cases are autosomal dominant);
• Congenital cataract (commonly autosomal dominant but other inheritance patterns also occur);
• Marfan syndrome;
• Aniridia (66 % via autosomal dominant);
• Optic atrophy.

While you may inherit vision problems from one parent, the outcome often depends on the combination of genes from both sides. For autosomal dominant conditions, a child has a 50% chance of inheriting the disorder if one parent carries the dominant gene.

Eye Health in Kids: Signs of Inherited Vision Problems

Children may not be able to express vision difficulties, which is why parents must watch out for early signs of inherited eye conditions.

These are indicators to look out for in your children if you are a parent with certain hereditary eye conditions:

• Extreme sensitivity to light (Rare – Albinism);
• Bumping into objects (retinitis pigmentosa);
• Uncontrolled eye movements (nystagmus);
• Cloudy or white pupils (congenital cataract);
• Poor tracking or no eye contact (congenital cataract);
• Frequent squinting (astigmatism, strabismus);
• Difficulty in recognizing red/green colours (most common form of color vision deficiency in children).

Catching these symptoms early can prevent complications and support your child’s visual development. You should notify your child’s physician for additional testing if you observe any of these symptoms in your child.

Epigenetics and Vision: How Habits Affect Genetic Expression

Your genes play an important role in your health, but so do your habits.

Epigenetics refers to how your environment and lifestyle influence the way your genes are expressed. In contrast to genetic mutations, epigenetic changes are reversible and do not cause a change in how your DNA is arranged, but they can change how your body reads a DNA arrangement.

Nutrients influence how our genes behave-without changing the genes themselves. This means that certain nutrients can help our body regulate and express genes. Even better, in some cases, nutrients can reverse harmful changes or decrease our risk of inheriting genetic conditions linked to diseases.

Scientists have found that good nutrition may help slow down or reduce the risk of age-related diseases like age-related macular degeneration. 

Our habits can either positively influence our genes to slow down or reduce our risks of having vision diseases or negatively impact it to accelerate its expression of these diseases.

Can Lifestyle Choices Prevent Genetic Eye Conditions?

Not entirely; but they can help manage or delay them. While you cannot change your genes, a healthy lifestyle can influence how they are expressed, and may help with slowing or reducing their impact on people with inherited eye conditions.

Eating healthily, avoiding smoking, managing stress, and exercising regularly are some lifestyle choices that can reduce the risk of onset of these genetic conditions.

The Importance of Genetic Testing for Eye Disorders

Testing enables early treatment for vision problems and identifies at-risk family members. It’s especially useful for congenital eye conditions and complex diseases like glaucoma. Genetics offers several benefits, including early diagnosis, prevention of complications, identification of modifiable risk factors and personalized treatment plans.

Genetic testing also helps determine eligibility for clinical trials and guide family screening by identifying at-risk relatives. As a parent with a genetic or inherited eye disease, you must screen your child for any eye defects as soon as possible.

Advances in Gene Therapy for Inherited Eye Diseases

Gene therapy includes techniques that change a cell’s biological function for treatment. It works by introducing a new gene, replacing a faulty one, or disabling a disease-causing gene.

There is currently no cure for many eye diseases; they are best managed. By focusing on the underlying genetic causes of these disorders rather than just their symptoms, genetic therapy aims to buck the trend and may provide a long-term solution or even a cure.

Studies show that the first success of gene therapy for eye diseases was treating Leber’s congenital amaurosis (LCA2) by replacing the faulty RPE65 gene responsible for the condition. This condition is a rare genetic disorder that occurs in children at birth or in a few months of life. Luxturna is an example of a gene replacement therapy that is approved by the FDA for treating patients with IRDs that are caused by mutations of the RPE65 gene.

While this is not an exhaustive list of the strides that are being made in gene therapy for inherited eye disorders, it’s an indication that those with inherited eye diseases can look to the future with optimism.

When to Consult an Eye Specialist with Family History

Don’t wait! Schedule regular eye check-ups if family members have eye diseases. Early interventions improve outcomes for vision problems, including those linked to diabetic neuropathy.

What Genetics Reveal About Your Eyes

Understanding the link between vision and eye health can offer healthy insights into your eye care. From common refractive errors to serious conditions like glaucoma,, your family history reveals a lot about your eyes.

While you can’t rewrite your genes, you can protect your eyes through lifestyle choices like regular eye check-ups and getting the right treatment for vision problems when detected. This gives you a heads up and the best chance to protect your sight for years to come.

While genetics may influence your risk for vision problems, your daily habits—including the nutrients you give your eyes—can make a powerful difference. That’s why supporting your eye health with targeted nutrition is one of the smartest steps you can take, especially if vision issues run in your family.

Our eyes are among the hardest-working parts of the body, yet they’re often the most neglected when it comes to getting proper nutrition. Without proper nutritional support, our eyes naturally begin to strain harder to carry out their everyday normal functions we didn’t even think about in our youth. This is why we created Restore Vision, which harnesses the power of carotenoids and antioxidants to support vision health and clarity.

Click here to learn more about Restore Vision, our unique solution that provides nutritional support for tired eyes that work all day long. Its powerful combination of 7 multi-purpose ingredients works synergistically to calm, enrich, and nourish normal vision, providing clear and comprehensive eye health support.

Frequently Asked Questions

What genes are responsible for bad eyesight?

It’s often a combination of genetic variants that contribute to vision problems rather than a single one. However, research has identified over 350 genes associated with bad eyesight.

How early can genetic eyesight problems appear?

Genetic eye problems can appear as early as infancy or childhood. Some conditions, such as congenital cataract and retinoblastoma, can appear at birth.

Does wearing glasses make genetic eyesight worse?

There is no research or scientific proof that glasses worsen eyesight.

References

1. World Health Organization
2. Eyes
3. How the Eyes Work
4. Anatomy, Head and Neck: Eye Nerves
5. Optic System
6. Is Bad Eyesight Genetic?
7. American Optometric Association
8. The Science Behind Myopia
9. Understanding the complex genetics and molecular mechanisms underlying glaucoma
10. Functional Visual Loss
11. Physiology, Vision
12. Visual Acuity
13. Editorial: Genetic features contributing to eye development and disease
14. Genes and genetics in eye diseases: a genomic medicine approach for investigating hereditary and inflammatory ocular disorders
15. The Prevalence of Refractive Errors Among Adults in the United States, Western Europe, and Australia
16. Developments in Ocular Genetics: Annual Review
17. The Role of Genetics in Vision: Understanding Hereditary Eye Conditions.
18. Refractive Errors
19. High Myopia Prevalence across Racial Groups in the United States: A Systematic Scoping Review
20. Epidemiology and Burden of Astigmatism: A Systematic Literature Review
21. The American Association of Ophthalmology
22. Centers for Disease Control and Prevention
23. Mendelian Inheritance Rule
24. Age-related Macular Degeneration
25. From Nature to Nurture-How Genes and Environment Interact to Shape Behavior 
26. Autosomal Dominant Inheritance
27. Autosomal Recessive Inheritance
28. Epigenetics
29. Epigenetic Effects of Healthy Foods and Lifestyle From The Southern European Atlantic Diet Pattern: A Narrative Review
30. Genes and genetics in eye diseases: a genomic medicine approach for investigating hereditary and inflammatory ocular disorders
31. Gene Therapy
32. Advances in Gene Therapy For Diseases of The Eye
33. Luxturna