What Are Gray Eyes?
Gray eyes are a rare eye color, but most people are unaware that gray eyes are due to a genetic mutation. Ninety percent of the time, gray eyes are hereditary. Gray eyes can be caused by a mutation in one of two genes, one that controls the melanin production process and another that controls the production of iris pigment cells. Studies show the more amount of melanin, the darker the eye color will be, and the less melanin, the lighter. The most common colors are brown, blue-green, hazel, and gray. Gray eyes are a mix of blue and green tones, with a touch of blue at the center of each iris.
Gray eyes have many benefits as they make the eyes look more striking and beautiful and help protect the eyes from sun damage and other harmful effects of the sun. An individual with gray eyes can see better in low light conditions like night vision or reading glasses.
What Are the Different Shades of Grey?
People having gray eyes have different intensities of shades of gray. Shades of gray may vary from person to person and result in smoke color, dark gray, hazel, light gray, bluish-gray, or brownish gray. The bluish-gray color of the eyes is more common in women, while the greenish-gray color is more common among men. At times, it may be challenging to understand the exact shade of gray as, most of the time; it may depend on the surrounding lighting.
What Causes the Eyes to Become Grey?
Plenty of melanin pigments cause the iris to become dark, resulting in either the eyes' black to dark black color. Conversely, slightly less melanin may result in the eyes having lighter shades of black to brown color of the eyes. With gray eyes, the iris's outermost covering has much less melanin than the inner layers of the iris. So when the light hits the eye, the inner layer reflects the light. This reflection causes a cloud in the stroma, resulting in the iris's gray, blue, or green hue. In addition, these individuals have more collagen in the stroma (the layer between the two layers of the iris), which also affects how light scatters making them appear gray than blue. It is, however, the number of melanin pigments present that determines the color of the eye.
Which Genes Affect the Color of the Eyes?
Several genes influence the various combinations and concentrations of melanin. The OCA2 (a protein in the melanocytes) gene is the key to deciding eye color. Scientists have identified at least nine other genes involved in the production and distribution of pigments. For example, the HERC2 ( responsible for pigmentation) regulates the activity of the OAC2 gene as needed. Other genes that decide the eye color include ASIP, IRF4, SLC24A4, SLC24A5, SLC45A2, TPCN2, TYR, and TYRP1. Several permutations and combinations of these genes produce different variations of eye colors in individuals.
What Are the Benefits of Having Grey Eyes?
The following are the benefits of genetically having gray eyes:
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Less Risk of Vitiligo - Studies show people with gray eyes are at a lesser risk of vitiligo and other disorders accompanying vitiligo, such as type 1 diabetes, arthritis, and Crohn’s disease. This could also mean people are at a lesser risk of autoimmune diseases.
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Calm Personality - People with gray eyes usually exhibit calm personalities associated with good wisdom.
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Changing Colors - At times, infants born with gray eyes can develop increased melanin pigmentation in later stages of life. This helps them enjoy different eye colors.
Can Grey Eyes Cause Light Sensitivity?
Studies found that the melanin pigments in the eye protect the eyes by reducing the amount of sensitivity. People with gray eyes have fewer melanin pigments in the eye, which makes them more prone to light sensitivity. Individuals with lighter shades of eyes cannot deal with harsh lighting conditions and brighter environments. They may lose focus and may also quint when exposed to bright light. This condition is temporary and does not cause permanent effects like vision loss or long-term damage. Hence, people with gray, blue, or green eyes are often advised to use polarized lenses when outdoors to protect their eyes.
What Are the Risks Associated With Gray Eyes?
People with gray eyes could be at risk of other conditions due to reduced melanin.
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Light Sensitivity - People with gray eyes are more prone to light sensitivity, which could be disturbing outdoors. They may also be photophobic, which may cause temporary eye discomfort.
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Eye Cancer - Ocular melanoma is an eye cancer affecting the uvea (layer of the eye). It can cause vision loss and the spread of cancer cells. This occurs on chronic exposure to ultraviolet rays and reduced protection from the UV rays due to low melanin pigments (melanin helps to protect eyes from UV rays). Though this condition is rare, people with gray eyes are at a higher risk of developing ocular melanoma. Ophthalmologists often recommend wearing wide-brimmed sunglasses, polarized lenses, and caps to protect the eyes from bright light conditions, sunlight, and the damaging effects of ultraviolet light.
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Skin Cancer - Due to reduced melanin, gray eyes are often accompanied by fair skin. Since melanin protects from the sun’s ultraviolet rays, lack of melanin causes the skin to become devoid of this protection, making these individuals more susceptible to skin cancer. Fair skin people may also experience more sunburns and freckles on the skin, making them more prone to skin cancers. However, it is essential to understand that dark-skinned people are at a lower risk of skin cancer, but can still get one.
Conclusion:
Gray eyes are a rare phenomenon associated with several benefits. However, some risk factors could be related to individuals with gray eyes. Hence, people with lighter shades of eye color must be more careful and protect their eyes. People with gray, blue, or green eyes should wear protective eyewear to prevent the damaging effects of ultraviolet rays.
