How Much Melanin Is In Green Eyes?
- Pieter Maas
Your eyes aren’t blue (or green) because they contain pigmented cells. As Paul Van Slembrouck writes for Medium, their colour is actually structural – and it involves some pretty interesting physics. The coloured part of your eye is called the iris, and it’s made up of two layers – the epithelium at the back and the stroma at the front.
- The epithelium is only two cells thick and contains black-brown pigments – the dark specks that some people have in their eye is, in fact, the epithelium peeking through.
- The stroma, in contrast, is made up of colourless collagen fibres.
- Sometimes the stroma contains a dark pigment called melanin, and sometimes it contains excess collagen deposits.
And, fascinatingly, it’s these two factors that control your eye colour. Brown eyes, for example, contain a high concentration of melanin in their stroma, which absorbs most of the light entering the eye regardless of collagen deposits, giving them their dark colour.
Green eyes don’t have much melanin in them, but they also have no collagen deposits. This means that while some of the light entering them is absorbed by the pigment, the particles in the stroma also scatter light as a result of something called the Tyndall effect, which creates a blue hue (it’s similar to Rayleigh scattering which makes the sky look blue ).
Combined with the brown melanin, this results in the eyes appearing green. Blue eyes are potentially the most fascinating, as their colour is entirely structural. People with blue eyes have a completely colourless stroma with no pigment at all, and it also contains no excess collagen deposits.
This means that all the light that enters it is scattered back into the atmosphere and as a result of the Tyndall effect, creates a blue hue. Interestingly, this means that blue eyes don’t actually have a set colour – it all depends on the amount of light available when you look at them. Structural colouration also gives colour to butterflies, beef and berries,
It’s pretty mind-blowing stuff. Van Slembrouck writes for Medium : “Imagine that you could shrink yourself to a microscopic size and then climb through the mesh of fibres in the stroma. That’s where structural colouration is coming from and in the mesh are also strands of smooth muscle tissue that contract to dilate (expand) the pupil, pulling the inner edge of the iris toward the outer edge.
- When this happens, the stroma fibres slacken and may become wiggly as tension is released.
- This makes me wonder, does that slightly alter the colour of your eye as well?” Check out Van Slembrouck’s great story to find out how hazel and grey eyes get their colour, and also to check out his beautiful diagrams that explain structural colouring.
Do green eyes have melanin?
Green Eyes Trivia – 10 Fun Facts About Green Eyes –
- Green eyes are very rare. Green eyes are the most rare eye color in the world. Only about 2 percent of people in the world have naturally green eyes. Green eyes are a genetic mutation that results in low levels of melanin, though more melanin than in blue eyes. Green eyes don’t actually have any color. That’s right – strange but true! While green eyes appear that lovely shade of emerald to the outside observer, the irises themselves have no actual pigment. Similar to blue eyes, the color we perceive is a result of the lack of melanin in the iris.
- However, just for fun – here are some personality traits that have historically been associated with green eyes in fables and folklore: intelligence, passion, mysteriousness, creativity, jealousy, and great leadership skills.
- Grab your shades.
- Because green eyes have less melanin than brown eyes, people with green eyes are more likely to be extra sensitive to UV rays.
- Rowling • Mary Jane Watson – The Amazing Spider-Man comics • Batgirl – DC Comics • Catwoman – DC Comics • Loki – Marvel Comics • Petyr Baelish – A Song of Fire & Ice by George R.R.
- Martin • Scar – The Lion King • Jane Eyre – Jane Eyre by Charlotte Bronte • Rapunzel – Disney’s Tangled • Asami Sato – Legend of Korra Green eyes don’t affect LASIK candidacy.
The less melanin in the iris, the more light scatters out, which makes the eyes look green. Ever heard from someone that their eyes change color? Turns out, it’s somewhat true. Changes in light make lighter eyes look like they are changing colors, sort of like a chameleon. Where in the world are the most green eyes? The highest concentration of people with green eyes is found in Ireland, Scotland, and northern Europe.
In fact, in Ireland and Scotland, more than three-fourths of the population has blue or green eyes – 86 percent! Many factors go into having green eyes. Sixteen separate genes have been identified as contributing to eye color. So, no matter what eye color your parents have, yours could end up being just about any color. Green eyes naturally occur in all races of people. Liqian, China is a hot spot for green eyes. There is a village in China called Liqian, in which two-thirds of all inhabitants today have green eyes and blonde hair. Green eyes and blonde hair are a rare combination. The high concentration of green-eyed, blond-haired people in Liqian is thought to be linked to their ancestry. Can green eye color affect personality? This particular topic may all be in the eye of the beholder (punny, huh?). There is no scientific data to prove that eye color is a factor in determining personality, and we will go on record as saying eye color does not affect personality.
The more melanin, the better protection from the sun – eye pigment literally protects the retina. Like blue-eyed people, those with green eyes are more sensitive to sudden increases in light. Green eyes are popular in pop culture. Green eyes may be the most rare of all natural eye colors, but you’ll see green peepers all over the silver screen. Green eyes are also incredibly popular in books. Some well-known green-eyed characters in books and movies include: • Harry Potter – from the Harry Potter book series by J.K.
No significant link has been found between eye color and quality of vision. Green-eyed people can have myopia (nearsightedness), astigmatism, or hyperopia (farsightedness), just like people with any other eye color. Green-eyed people can also have LASIK vision correction,
Your Eyes Deserve the Best We hope you enjoyed our top 10 trivia facts about green eyes. Whatever your eye color, you’ll no doubt agree vision is one of the most treasured senses. Your eyes are your window to the world. That’s why you shouldn’t settle for anything less than your best vision possible.
- If you’re currently dealing with the nonstop hassle of foggy glasses or uncomfortable contacts, give our world-class experts a call.
- Ugler Vision has been voted Best of Omaha #1 LASIK provider for four consecutive years, and we’d love for you to come in and see the Kugler Vision difference for yourself.
Book your EyeAnalysis assessment today online, or call us at 402-558-2211 to learn about your LASIK options. See you soon! Lance Kugler, MD, is a specialist in LASIK and vision correction surgery and CEO of Kugler Vision, A proud Omaha native, he is passionate about improving lives through clear vision. Dr. Kugler serves on several national boards, and his practice is recognized internationally as a center of excellence.
- Dr. Kugler is one of the original founders of the Refractive Surgery Alliance, an international organization comprised of over 350 of the world’s leading vision correction surgeons; he also served as its first president.
- In 2019, Dr.
- Ugler was selected as a TEDx speaker, and delivered a talk in Omaha about the worldwide epidemic of nearsightedness and refractive solutions.
Dr. Kugler is an Associate Professor of Refractive Surgery at the University of Nebraska Medical Center’s Truhlsen Eye Institute, has been published in many medical journals, and participates in numerous clinical studies to advance the field of vision correction surgery.
What eye color has most melanin?
Is eye color determined by genetics? A person’s eye color results from pigmentation of a structure called the iris, which surrounds the small black hole in the center of the eye (the pupil) and helps control how much light can enter the eye. The color of the iris ranges on a continuum from very light blue to dark brown.
Most of the time eye color is categorized as blue, green/hazel, or brown. Brown is the most frequent eye color worldwide. Eye color is determined by variations in a person’s genes. Most of the genes associated with eye color are involved in the production, transport, or storage of a pigment called melanin.
Eye color is directly related to the amount of melanin in the front layers of the iris. People with brown eyes have a large amount of melanin in the iris, while people with blue eyes have much less of this pigment. A particular region on plays a major role in eye color.
Within this region, there are two genes located very close together: and HERC2, The protein produced from the OCA2 gene, known as the P protein, is involved in the maturation of melanosomes, which are cellular structures that produce and store melanin. The P protein therefore plays a crucial role in the amount and quality of melanin that is present in the iris.
Several common variations (polymorphisms) in the OCA2 gene reduce the amount of functional P protein that is produced. Less P protein means that less melanin is present in the iris, leading to blue eyes instead of brown in people with a polymorphism in this gene.
A region of the nearby HERC2 gene known as intron 86 contains a segment of DNA that controls the activity (expression) of the OCA2 gene, turning it on or off as needed. At least one polymorphism in this area of the HERC2 gene has been shown to reduce the expression of OCA2 and decrease P protein production, leading to less melanin in the iris and lighter-colored eyes.
Several other genes play smaller roles in determining eye color. Some of these genes are also involved in skin and hair coloring. Genes with reported roles in eye color include ASIP, IRF4, SLC24A4, SLC24A5,, TPCN2,, and, The effects of these genes likely combine with those of OCA2 and HERC2 to produce a continuum of eye colors in different people.
Researchers used to think that eye color was determined by a single gene and followed a simple inheritance pattern in which brown eyes were dominant to blue eyes. Under this model, it was believed that parents who both had blue eyes could not have a child with brown eyes. However, later studies showed that this model was too simplistic.
Although it is uncommon, parents with blue eyes can have children with brown eyes. The inheritance of eye color is more complex than originally suspected because multiple genes are involved. While a child’s eye color can often be predicted by the eye colors of his or her parents and other relatives, genetic variations sometimes produce unexpected results.
Several disorders that affect eye color have been described. is characterized by severely reduced pigmentation of the iris, which causes very light-colored eyes and significant problems with vision. Another condition called affects the pigmentation of the skin and hair in addition to the eyes. Affected individuals tend to have very light-colored irises, fair skin, and white or light-colored hair.
Both ocular albinism and oculocutaneous albinism result from mutations in genes involved in the production and storage of melanin. Another condition called heterochromia is characterized by different-colored eyes in the same individual. Heterochromia can be caused by genetic changes or by a problem during eye development, or it can be acquired as a result of a disease or injury to the eye. Sturm RA, Duffy DL, Zhao ZZ, Leite FP, Stark MS, Hayward NK, Martin NG, Montgomery GW. A single SNP in an evolutionary conserved region within intron 86 of the HERC2 gene determines human blue-brown eye color. Am J Hum Genet.2008 Feb;82(2):424-31. doi: 10.1016/j.ajhg.2007.11.005.
- Epub 2008 Jan 24. PubMed:,
- Free full-text available from PubMed Central:,
- Sturm RA, Larsson M.
- Genetics of human iris colour and patterns.
- Pigment Cell Melanoma Res.2009 Oct;22(5):544-62.
- Doi: 10.1111/j.1755-148X.2009.00606.x.
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- Genotype-phenotype associations and human eye color.
J Hum Genet.2011 Jan;56(1):5-7. doi: 10.1038/jhg.2010.126. Epub 2010 Oct 14. Review. PubMed: : Is eye color determined by genetics?
Do green or blue eyes have less melanin?
Blog 1. Only 8 Percent of the World’s Population Has Blue Eyes If you have got blue eyes, you might just belong to one of the world’s most exclusive groups without realising it! Since blue eyes are genetically recessive, only 8 percent of the world’s population has blue eyes.
- While blue eyes are significantly less common than brown eyes worldwide, they are frequently found from nationalities located near the Baltic Sea in northern Europe.2.
- There is No Blue Pigment in Blue Irises The colour of our eyes depends on how much melanin is present in the iris.
- Blue eyes get their colour the same way water and the sky get their blue colour — they scatter light so that more blue light reflects back out.
The iris is made up of two layers. For almost everyone — even people with blue eyes — the back layer (called the pigment epithelium) has brown pigment in it. The front layer of the iris (called the stroma) is made up of overlapping fibers and cells. For people with brown eyes, some of the cells also have brown pigment in them.
If there is no pigment at all in this front layer, the fibers scatter and absorb some of the longer wavelengths of light that come in. More blue light gets back out and the eyes appear to be blue.3. Blue Eyes are More Sensitive to Light Melanin in the iris of the eye appears to help protect the back of the eye from damage caused by UV radiation and high-energy visible “blue” light from sunlight and artificial sources of these rays.
Since blue eyes contain less melanin than green, hazel or brown eyes, photophobia is more prevalent in blue eyes compared to darker coloured eyes. For these reasons, having less melanin in your irises means that you need to protect your eyes more from the sun’s UV rays.
- Therefore, it is recommended to those with blue eyes to stay out of the sun for long periods of time and try to wear protective eyewear when you are outdoors.4.
- All Blue-Eyed People May Have A Common Ancestor Originally we all had brown eyes, however, according to researchers at the University of Copenhagen, it appears that a genetic mutation in a single individual in Europe 6,000 to 10,000 years ago led to the development of blue eyes.
Therefore, we can conclude that this genetic mutation is the cause of eye colour of all blue-eyed humans alive on the planet today. What is the genetic mutation? A genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a “switch”, which “turned off” the ability to produce brown eyes.
The OCA2 gene codes for the ‘P protein’, which is involved in the production of melanin (the pigment that determines the colour of our eyes, skin and hair). The “switch”, does not, however, turn off the gene entirely, but rather limits its action to reducing the production of melanin in the iris – effectively “diluting” brown eyes to blue.
According to Hans Eiberg, associate professor in the Department of Cellular and Molecular Medicine from the University of Copenhagen, “From this, we can conclude that all blue-eyed individuals are linked to the same ancestor. They have all inherited the same switch at exactly the same spot in their DNA.” 5.
Blue Eyes at Birth Doesn’t Mean Blue Eyes For Life While blue eyes may be rare, they’re among the most common eye colours at birth. Since the human eye does not have its full adult amount of pigment at birth, most Caucasian babies are born with blue eyes. However, since human melanin tends to develop over time — this causes the child’s eye colour to change as more melanin is produced in the iris during early childhood.6.
People With Blue Eyes May Have a Higher Risk of Alcoholism A new study suggests that individuals with blue eyes are at a higher risk for alcohol dependency compared to those with darker eyes. Therefore, this finding adds further evidence to the idea that alcoholism has a genetic component.
A study published in American Journal of Medical Genetics, Part B: Neuropsychiatric Genetics found that European Americans with blue eyes had up to 83 percent higher odds of becoming dependent on alcohol, compared with matched controls who had darker eye colours. This research suggests that alcoholism has a genetic component linked to genetic sequences that determine eye colour, which may help explain the association.
However, at this stage, the reason for the correlation is still unknown and further research is required to fully understand this correlation in the findings.7. You Can’t Predict the Colour of Your Child’s Eyes Since it was once believed that eye colour — including blue eyes — was a simple genetic trait, many people used to believe that blue-eyed people could only have blue-eyed children.
- Before geneticists fully understood how human eye colour inheritance works, a child’s eye colour to used be used as a paternity test — based on the assumption that you could predict a child’s eye colour if you knew the colour of the parents’ eyes and perhaps the colour of the grandparents’ eyes.
- But geneticists now know that this concept is far more complicated, as eye colour is influenced by an interaction of as many as 16 different genes — not just one or two genes as once thought.
Additionally, the anatomic structure of the iris can also influence eye colour to some degree. In summary, it’s impossible to know for sure if your children will have blue eyes. Even if you and your partner both have blue eyes, that’s no guarantee your child’s eyes will also be blue.
Which eye has least melanin?
– Scientists used to think your eye color was determined by two eye color genes, one from each parent. Since the gene for brown is dominant over blue, the belief was a blue-eyed person would have two genes for blue eyes, and two blue-eyed parents couldn’t have a brown-eyed child.
We now know that it’s much more complicated than that. According to an older 2010 study, your eye color is determined by up to 16 genes that control melanin production in your iris. Melanin absorbs light. When an object absorbs light, it looks dark. When it doesn’t absorb light, the light is reflected, and the object is the color of the light it reflects.
Light reflected from your eye comes from the blue part of the color spectrum. Brown eyes have a lot of melanin, so they absorb light, which makes them dark. Hazel eyes have less melanin than brown eyes but more than green eyes. Blue eyes have the least amount of melanin and reflect the most light.
What eye color has no melanin?
What is the most common eye color? – About 10,000 years ago, everyone in the world had brown eyes. Scientists believe that the first blue-eyed person had a genetic mutation that caused the body to produce less melanin. Today, about half of the people in the United States have brown eyes.
Amber, which some people describe as copper, gold or very light brown. Blue or gray, which occurs when someone has no pigment (melanin) in the front layer of the iris. Around 1 in 4 people in the U.S. have blue eyes. Brown, which is the most common eye color in the world. Green, which is the least common eye color. Only 9% of people in the United States have green eyes. Hazel, a combination of brown and green. Hazel eyes may also have flecks or spots of green or brown. In the U.S., about 18% of people have hazel eyes.
Who has high melanin?
Abstract – We have examined the quantity and composition of melanin in both photoprotected (volar upper arm) and chronically photoexposed (dorsal forearm) skin from a range of different ethnic skin types including African, Indian, Mexican, Chinese and European. The most lightly pigmented (European, Chinese and Mexican) skin types have approximately half as much epidermal melanin as the most darkly pigmented (African and Indian) skin types. However, the composition of melanin in these lighter skin types is comparatively more enriched with lightly coloured, alkali-soluble melanin components (up to three-fold). Regardless of ethnicity, epidermal melanin content is significantly greater in chronically photoexposed skin than it is in corresponding photoprotected skin (up to two-fold). However, by comparison there is only a modest enrichment of lightly coloured, alkali soluble melanin components in photoprotected skin (up to 1.3-fold). Analysis of melanosomes extracted from the epidermis in these subjects indicates that the proportion of spheroidal melanosomes is low in all skin types examined (<10%). This suggests that in human skin, pheomelanin is a very minor component of epidermal melanin, even in the lightest (European) skin types. Analysis of melanosome size revealed a significant and progressive variation in size with ethnicity: African skin having the largest melanosomes followed in turn by Indian, Mexican, Chinese and European. On the basis of these findings, we propose that variation in skin pigmentation is strongly influenced by both the amount and the composition (or colour) of the melanin in the epidermis. Variation in melanosome size may also play a significant role. However, the data also suggest that in human skin there are subtle differences in the mechanisms associated with the maintenance of constitutive pigmentation and facultative hyperpigmentation, respectively.
Do grey eyes have melanin?
Gray – Close to 3% of the world’s population have gray eyes. People with gray eyes have little or no melanin in their irises, but they have more collagen in a part of the eye called the stroma. The light scatters off the collagen in a way that makes the eyes appear gray.
What color is melanin in eyes?
Melanin and Pigment Types – There are two different types of melanin a person could have in their irises : eumelanin, which produces a rich chocolate brown color, and pheomelanin, which produces a range of amber, green, or hazel colors. Blue eyes, on the other hand, get their color from having relatively little eumelanin.
The pigment itself isn’t blue, but the way the light scatters around the front layer of the iris ends up appearing blue — the same way the sky appears blue! Green eyes come from a combination of both types of melanin in low enough levels to also get a bit of the light scattering effect. Hazel eyes have enough melanin that they don’t get the light scattering effect.
Red and “violet” eyes (very rare) come from having almost no melanin at all, so you actually see the color of the underlying blood vessels or it combines with the light scattering effect to produce violet. This is typical in albinism.
What pigment makes green eyes?
Green – Green eyes probably result from the interaction of multiple variants within the OCA2 and other genes. They were present in south Siberia during the Bronze Age, Green eyes are most common in Northern, Western and Central Europe, In Scotland, 29% of people have green eyes. Around 8–10% of men and 18–21% of women in Iceland and 6% of men and 17% of women in the Netherlands, have green eyes. Among European Americans, green eyes are most common among those of recent Celtic and Germanic ancestry with about 16%.
Are green eyes just brown?
Green eyes – If you have green eyes, you’re in luck. In addition to being the rarest eye color among Americans, green eyes are the most attractive, according to 66,000 people who voted in our survey, Just how rare are green eyes? Fewer than one out of every 10 Americans (9%) has them.
But why are green eyes so rare? Surrounding each pupil, the colored portion of our eyes is called the iris, A pigment called melanin is responsible for that color — the same pigment that determines the color of our skin. And just like our skin, less melanin means lighter colors, while more melanin equals darker colors.
Every eye color — yes, even green — is actually some shade of brown, thanks to the melanin inside the iris. Light bounces off this melanin in different ways and creates a sort of optical illusion, allowing us to see vibrant greens and blues. Iris color is determined by our parents’ eye colors mixed with a little genetic lottery.
- Green irises have an uncommon melanin level — less than “truly” brown eyes, but more than blue eyes.
- This is why green eyes are so unique.
- And while 9% is indeed rare, green eyes have an even lower eye color percentage across the globe.
- Only 2% of the world’s population has green eyes, according to the demography resource World Atlas.
SEE RELATED: How eye color develops and why it changes
|Do you have light-colored eyes?|
|Green eyes are the rarest, globally speaking. But they’re not necessarily the rarest in all parts of the world. Wherever you reside, lighter eyes (like green) are more sensitive to the sun. Those with light-colored eyes are also more likely to experience vision problems. So get those gorgeous green eyes in to see a local eye doctor today. And be sure to keep up with routine eye exams.|