Determining your true eye color can be confusing. The color we see in the mirror or read on our driver’s license may not match the eye color others see or what an eye doctor would determine. This is because eye color is complex, can change over time, and is often some blend of shades and hues. By understanding the factors that influence eye color and how to properly assess it, you can get to the bottom of your true eye color.
Genetic Factors
Genetics play a major role in determining eye color. The main gene that controls eye color is the OCA2 gene, which is found on chromosome 15. This gene produces a protein that helps produce the pigment melanin. Melanin is what gives color to your irises. The amount and type of melanin your body produces is determined by the allele variations you inherit from your parents.
There are two main alleles related to eye color:
– The “brown” allele which produces a lot of eumelanin, a brown pigment. This results in brown eyes. This is dominant over other colors.
– The “blue” allele which produces low levels of melanin and less eumelanin. This results in blue eyes or green eyes depending on other factors. This is recessive.
Other genes also impact eye color to a lesser degree, contributing to the final blend of melanin and overall color that develops. But in general, brown eyes are dominant and blue/green eyes are recessive. Having two brown alleles results in brown eyes while having one brown and one blue/green allele leads to an intermediate eye color.
Amount of Melanin
The total amount of melanin present affects the shade of your eye color. Higher melanin levels lead to darker eyes, while lower levels cause lighter eyes. Melanin amount is primarily determined by genetics, but can also be impacted by:
– Age – melanin levels may decline over time, causing the eyes to lighten somewhat.
– Injuries – trauma to the eye can reduce melanin production.
– Medications – some drugs are associated with changes in melanin levels.
– Environment/lifestyle – extended sun exposure and smoking may increase melanin.
So even with the same genetic profile, the exact shade of your eyes can vary over time as melanin levels change.
Ratio of Eumelanin to Pheomelanin
The relative levels of the two types of melanin also impact eye color:
– Eumelanin – A brown pigment that produces brown and black hues.
– Pheomelanin – A red pigment that produces yellow and orange hues.
Higher eumelanin to pheomelanin ratios will result in brown eyes. Lower ratios lead to green, hazel, amber, and yellow-toned eyes. This ratio is primarily genetically determined. But sun exposure can break down pheomelanin which may make the eyes look slightly browner over time.
Stroma and Light Scattering Effects
The stroma is the collagen-rich tissue structure of the iris that gives it form and texture. The composition and density of the stromal tissue impacts how light scatters and reflects off the iris, influencing the final color we perceive.
Those with lighter eye colors tend to have less dense irises that allow more light to pass through and scatter. This amplifies the Rayleigh scattering effect that makes the sky look blue. It is the same effect that makes blue and green eyes appear lighter.
Denser iris tissue blocks more light and results in darker brown eyes. The exact thickness and density of stromal tissues are genetically determined.
Assessing Your Eye Color
With all these factors impacting eye color, how do you determine your true shade? Here are some tips:
– Examine your eyes in natural daylight – artificial lighting can distort color. Go outside on a clear day and look at your eyes in the shade, away from any strong light sources. This will give you the most accurate colors.
– Have someone else observe your eye color up close under natural light.
– Look closely for any flecks, rings, or heterochromia (two different colored eyes) which indicate blended genetics.
– Check for any color changes towards the rim or inner areas of the iris compared to the overall color.
– Note how your eyes compare to family members’ eye colors since you share genetic backgrounds.
– See an ophthalmologist and have them formally document your eye color.
– Use photo editing software like Photoshop to analyze subtle shades in closeup photos of your eyes.
Common Eye Colors
Here are some of the most common true eye colors and their typical genetic and melanin profiles:
| Eye Color | Genetics | Melanin Level | Melanin Ratio |
| Brown | Two brown alleles | High eumelanin | Mostly eumelanin |
| Hazel | One brown, one blue allele | Moderate eumelanin | Mix of eumelanin and pheomelanin |
| Amber | One brown, one blue allele | Low to moderate eumelanin | More pheomelanin |
| Green | Two blue alleles | Low eumelanin | Mostly pheomelanin |
| Blue | Two blue alleles | Very low melanin | Little eumelanin |
As you can see, subtle genetic, melanin, and structural factors intersect to determine true eye color. So if your eyes seem to change between different shades of green, hazel and brown, you likely have a mix of genetic influences at play. The tone can evolve over time too. But with a careful eye and assessment in proper lighting, you can get to the bottom of your eye color.
Impacts of True Eye Color
Does your specific shade of green versus hazel actually matter beyond aesthetics? Here are some potential impacts:
– Identity – Your eye color can shape your sense of self and how you are visually identified.
– Ancestry – Eye colors like blue and green point to European heritage while dark brown eyes indicate African or Asian roots.
– Health conditions – Some eye diseases are linked to melanin levels and genetics associated with color.
– Reactions to drugs – Certain medications deposit pigment into light colored eyes more readily.
– Vision quality – There are mixed findings on minor vision differences between eye colors.
– Sensitivity to light – Darker eyes may handle sunlight glare better while lighter eyes see better in dim conditions.
– Perceived personality – There are associations between eye color and assigned personality traits.
So while subtle changes in hue do not matter much, overall darkness versus lightness of eyes can have medical and social implications.
Can Your Eye Color Change Permanently?
For most people, the eye color they are born with remains relatively stable throughout life. But in some cases more noticeable, permanent shifts can occur:
– Trauma – Significant blunt force injury to the eye area can damage the iris and alter melanin content.
– Medications – Certain drugs like latanoprost eye drops for glaucoma can gradually darken the iris by increasing melanin levels.
– Pigment deposition disorders – Excess pigment release in the eye can lead to dark spots on the iris.
– Pigment loss conditions – Issues with melanin production like ocular albinism or iris transillumination can lighten the iris.
– Aging – Over decades, the balance of melanin types may change slightly lightening or darkening eyes.
– Hormones – Pregnancy hormone changes are linked to lightening of eyes for some women.
So while genetics determine the majority of eye color, in rare cases circumstances can override programming and cause a noticeable shift in shade that sticks.
Can You Change Your Eye Color Artificially?
While eye color is mostly set by nature, there are ways to artificially change the appearance of your eyes:
– Contacts – Colored contact lenses that cover the iris are the easiest way to temporarily change eye color.
– Eye tattoos – Inking the whites of the eyes or top layer of the iris can permanently alter color. Dangerous procedure.
– Lasers – Non-invasive lasers can lighten parts of the iris without pigment loss by targeting deeper melanin layers. Minimal effect for most people.
– Surgery – Implanting colored implants onto the iris with synthetic fibers is an option for permanent color change. High risk of complications.
Of these, colored contacts are the only widely used and safe method to artificially shift eye color temporarily. All other techniques involve permanent risks and often do not achieve significant results.
What’s the Rarest Eye Color?
Most people have brown, blue, or hazel eyes. The rarest eye colors include:
– Gray eyes – A darker gray-blue hue due to low melanin levels and muted pigmentation. Only 1-2% of people have true gray eyes.
– Green eyes – About 2% of the population has green eyes, more common among Northern and Central Europeans. Jade green is exceptionally rare.
– Amber eyes – A golden hue resulting from a low melanin ratio. Around 1% of people have this color, more common in parts of Asia.
– Red/violet eyes – An extremely rare eye color caused by albinism and lack of melanin production. Only a handful of people worldwide exhibit this hue.
– Heterochromia – Having two different colored eyes, like one brown and one blue, only occurs in about 1 in 1,000 people.
So while uncommon, eye colors besides brown are not as exceptionally rare as some may think. But the most vibrant, vivid versions of these shades are quite unique.
Conclusion
It takes a nuanced evaluation taking into account genetics, melanin levels, structural components, and lighting conditions to determine true eye color accurately. The color perceived in a quick glance can be deceiving. But with some self-assessment, help from others, and documentation under ideal conditions, you can get to the bottom of your true eye color which may differ from what you expect. This can provide insight into ancestry, vision performance, aesthetics, and health factors tied to your eyes’ unique biology.
