Hazel Eyes and Genetics

Written by: Rafael • Edited by: Paul Arnold
Updated Sep 30, 2009 • Related Guides: Chromosomes

Very little is known about the genetics of hazel eyes. Whilst biology can explain blue, brown and green eyes, it's left to theoretical models to fill in the gaps for hazel eye color.

What are Hazel Eyes?

The definition of hazel eyes varies. For some, hazel eyes range from a light brown to a medium golden-green. In North America, "hazel" is a term used to describe eyes that appear to change color, ranging from light brown to green and even gray, depending on lighting in the environment.

Characteristics of Hazel Eyes

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A large percentage of hazel eyes have a brown ring around the iris, and either green or blue coloring around the outside of the ring. In the image to the right, you can see the darker inner ring surrounded by a lighter outer ring. To learn more about the subject, read about how genetics affect eye color.

Common Eye Colors

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The most common color of eyes is brown and the least common green. There is a variety of colors and shades in between. There are also some unusual eye colors such as red and violet. Brown, green and blue eye color comes from a pigment called melanin. Brown eyes have a lot of melanin in the iris, green eyes have less, and blue eyes have little or no pigment.

Two genes, bey2 and gey, work together to make brown, green, or blue eyes. Each gene has two versions or alleles. One form of bey2 makes lots of melanin (and is usually referred to as B) while the other form makes only a little (b). One form of gey makes some melanin (G) while the other makes only a little (b). Considering these two genes, and the fact that people have two copies of a gene; one from mom and one from dad, then we have the following possibilities for various eye colors:

Brown eyes (BB bb, BB Gb, BB GG, Bb bb, Bb Gb, Bb GG)

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Green (bb GG, bb Gb)

Blue (bb bb)

The bey2 and gey genes are names of theoretical genes on chromosome 15 that helps explain some of the genetics of eyes colors. Recent studies have discovered that the bey2 gene is actually the OCA2 gene.

The Genetics Behind Hazel Eyes

The genetics of hazel eyes is not clear yet and has received little research attention. There are only models that try to explain it. One model is explained by Dr. Barry Starr, from Stanford University. However, it is only a model and many others may surface soon.

According to Dr. Starr, a new gene (yet to be found) could be a modifier gene of the gey gene. This gene, named M could produce hazel eyes by having the gey make more melanin. As with any gene, the M gene comes with two alleles, the M which increases the amount of melanin gey makes and the m which has no effect.

Studying the possible combinations of the G (gey) and the M (modifier) genes it would be possible to explain (theoretically) hazel eyes. Anytime you get the G with the M gene you will get hazel eyes (according to this model). So, if a person has the following combinations: GGMM, GbMM, GGMm, and GbMm he (or she) will have hazel eyes. If the person has GGmm and Gbmm he will have green eyes and if he (or she) has bbMM, bbMm, or bbmm he or she will have blue eyes.

Hazel eye color genetics will of course become clearer one day, but for the moment it's models such as Starr's that give us the best insights.

Genetics is also responsible for human characteristics such as blue eyes, blonde hair, and red hair.

Sources

Genetic determinants of hair, eye and skin pigmentation in Europeans. By Patrick Sulem et al. Nature Genetics 39, 1443 - 1452 (01 Dec 2007)

Dr Barry Starr (http://www.thetech.org/genetics/ask.php?id=126).

kayla Feb 4, 2012 2:17 PM

RE: Hazel Eyes and Genetics

My eye color is hazel, because everywhere i go go everybody says omg!! you have such pretty eyes and im like thanks.So i believe my eyes r pretty because thier big and they stand out like marbles!!

Ash Nov 20, 2011 1:00 AM

My eyes are two completely different colors. One is a brown/green hazel color which i get from my mother and the other eye is a dark brown/black color that i get from my father's eyes, except about an 1/8 of it is a section of hazel.

Cookie Aug 8, 2011 9:57 PM

hazel eyes

My mom had hazel eyes and was of Jewish/Austrian extraction. My dad and light blue/gray eyes and Polish.
My eyes are golden green with an olive green rim. I've been told that's a sign of Gypsy blood and common in Eastern Europe.

Ked May 29, 2011 2:29 PM

eyes

my eyes are brown around the iris, then around the brown, yellow and around the yellow grayish-green. is my eye color hazel?

Anonymous May 24, 2011 3:36 PM

i have always wondered what myy eye color is.. they are yellowish around the pupil and then green with a a dark blue circle around the green

Sue May 22, 2011 3:07 AM

Eye Color

My four grandparebts had:
1. Blue
2. Hazel
3. Green
4. Brown
I da a green-eyed mother and a hazel eyed (really gray, hreen and brown mixed color) father. I look just like my dad but have medium, reddish brown eyes. Eye color inheritance is obviously more complex than we previously thought.

Lauren Apr 20, 2011 5:22 PM

Hazel eyes

The color of my eyes varies by the light. In natural light, they are equal parts olive green and rich brown, in artificial light the green gets deeper and there is more of it. I havae some gray right inside the outer ring, which is very defined.

iNerd Mar 30, 2011 1:23 PM

my eyes :D

so i have green eyes
my dad has green eyes and my mom has blue eyes
my grandma has blue eyes my other grandma has brown my grandpa has blue and my brother has green but one of his eyes has a slight spot of brown to the side its a straight line of it but only on one eye..my sister has blue eyes and my half siblings all have brown can u explain this to me?

shauna Mar 19, 2011 3:28 PM

dad's hazel + mum's browns

My dad's father and mother both have dark brown eyes and are of Asian ethnicity. Everyone on my dad's side has light brown eyes but my dad is the only one with hazel. It's a thin dark brown ring on the outside, they get green/grey in the middle and are brown around the pupil.
My mother has dark brown eyes. As a result, I guess it makes light brown eyes, like mine (but my brother has dark brown, almost black, eyes)...Weird.

Katherine K Mar 2, 2011 8:45 AM

Hazel eye

My family all have blue yes,I have greeny-yellow.

Ioan Feb 24, 2011 3:32 AM

Hazzel

My dad has clear blue and mom, brownish I ended up having hazel!

moses Feb 19, 2011 3:32 PM

my hazel eyes

my eyes are pretty wierd.. they change color when i cry or when im sad..crying they turn a lighter green and sad they turn more brownish.. another wierd thing.. out of seven brothers and sisters.. im the only one with colored eyes.. and both parents have brown eyes

MAria Jan 17, 2011 1:00 PM

I have hazel eyes, I cant even describe what color they are most of the time, people that dont look at them really close think that they are brown, but at night or when Im tired or crying they turn green, I have golden brown and green in them, so I guess most of the time they are golden brown....my mother has brown eyes and my father has green eyes turning to gray so I guess it was a mix between them, my sister has brown eyes, Im the only one with hazel eyes.

marian feliz Dec 21, 2010 9:43 PM

ma eyes

my eyes are hazel and im the only one in my family that has hazel eyes coz ma dad has light brown eyes and my mom dark brown so for some reason i got hazel eyes :)

jem gal Nov 23, 2010 11:24 PM

Woke up one night to my son and his pal shining a light in my eyes. My sons friend thought I was a witch because of my "weird" eye color. no one in my family has hazel or green eyes. My eyes change if I wear green they become green. Where do they come from? A recessive gene?

Aleksandra Nov 17, 2010 3:48 PM

My eyes are mix of reddish brown (around the pupil), dark olive green (inside), and a dark charcoal (around the iris). I love my eyes))

Cierra Nov 13, 2010 1:00 AM

My eyes

my grandparents have blue eyes my mom has brown eyes. my dad has dark hazel eyes as well as my grandpa. i have hazel eyes. there have a smoky grey outline around the iris and a green ring on the farthest ring. then a golden-brown ring closet to the pupil. they change from looking brown to dark green depending on what eyeliner i use and the lighting. i feel very lucky i have different eyes than everyone else.

Lisa Nov 7, 2010 6:47 PM

My eyes go from green to gold... what is with that?

synapticgate Oct 12, 2010 6:51 PM

Hazel Eyes

My mom had pale green eyes, green to grey. My dad's are sort of a copper penny brown....Mine are hazel, leaning more towards an emerald green....bizarre looking.

philip watkins Oct 8, 2010 2:27 PM

Me and my father are the only ones that has hazel eyes. However my mother and my other brothers and sisters has drak brown eyes. I always wonder if some one in my family has either green or perhaps blue eyes.

Janna-Rose Landers Sep 21, 2010 1:47 AM

My Hazel Blue Eyes

My parents have blue & green eyes & my 2 brothers have Kelly green eyes like Daddy. Mine usually are blue like mums except for when I'm sad or on rainy days are dark gray. When I'm excited or just happy they look more like a sky blue this seems weird but it happens. My Nana also has similar color so maybe it's her I inherited this color from
Thanks.~~JaNNa~~

Stephen Sep 15, 2010 7:56 AM

My Hazel Eyes

I have hazel eyes along with my sister (mine ones are brighter than hers) but our parents have both brown eyes. My grandparetns have all blue eyes so I think that we got hazel eyes cause of a mix of blue and brown eyes. I like them so much but I hate the fact that in cloudy days they look light brown and not green :/ Anyway I love them!

Gaby Sep 14, 2010 2:02 AM

gorgeous eyes

i have gorgeous hazel eyes which i inherited from my grandparents and its great ppl always give me compliments of my eyes and i feel very lucky to have them

sherry Sep 12, 2010 5:16 PM

my eyes

when I was born, my eyes were a dark grey. then they went to blue, brown, and now hazel. I like my eyes :)

Karla L. Aug 23, 2010 4:52 PM

I have pretty interesting eyes!

My eyes are hazel - multicolored. They have a black ring around the iris, inside they are light golden-green, and around the pupil they are brown. They are very interesting and beautiful and I've had a lot of compliments for ithem. The color is kind of expected because my dad has clear green eyes and my mom has brown. They often change color too - in the sun they are a beautiful shade of golden-green. I love hazel eyes! :D

Andre Aug 5, 2010 6:44 PM

Yesmy hazel eyese

my eyes change from dark brown to amber. Their weirddd!!!

Meg Jul 23, 2010 10:39 AM

When I was a baby my eyes were dark blue as all newborns are and then they changed to blue somewhere around the time I turned three they went green and then hazel. In the dark my eyes look light brown but in the light they look gold brown with a green ring on the outside.

Lauren Jul 9, 2010 8:30 AM

GLOWING EYES!

My best friend has the most alluring eyes i have ever seen! he has a yellow ring around the iris and then this mix of emerald and lime green colour of the rest of the eye, it is amazing to look at!!!
My other friend has blueish green eyes with what lookes like craters in her eye, which we find quite strange but yet interesting :)
And sadly for me i have boring brown eyes :(

Amber Jul 5, 2010 6:06 AM

My strange unidentifiable eyes

I as born with dark sapphire blue eyes, and they say if your born with dark blue eyes, your eyes will change colour. As i grew older, my eyes went from a green and then hazel. But unfortunately, they went brown....
BUT not the brown that your probably thinking of, in fact its more of a amber colour with splashes of gold in them. In fact, i have one eye amber with gold, and the other a reddish amber with orange. In certain lighting, my eyes are really vibrant and some people say they look hazel with green and gold (but thats only in one eye, the other looks more of a mahogany colour...)

There really strange and change... some people can't even tell if my eyes are hazel or amber or brown.... (they get so confused... :D)
Anyway, that is my story for you...

Darcy Jul 1, 2010 4:56 PM

My are hazel that change color on a daily basis. They turn blue, green, and brown. I have a blue-gray outer ring with green on the inside and a brown-amber inner ring. But what i don't understand are the dark brown spots in my iris. I have three total; a big one in my right eye and two small ones in my left. But no matter what color my eyes change, the spots don't change either. Why are they there?

Ali Jun 29, 2010 6:03 AM

My hazel eyes.

My eyes are very interesting. My dad has dark brown eyes and my mom has bright blue. So I kinda got a mixture of their colors. Mine have a yellow ring around the iris with green around the yellow and brown around the green. Odd, right? In pictures, they appear blue for some reason. But in person they appear yellow. But when you look at them very closely, they resemble what I described them to be. When I was little, I used to hate them because I thought they were boring, but I've really learned to appreciate their uniqueness. :3

Anonymous Jun 27, 2010 1:10 PM

my eyes sometimes go from greenish brown to a golden color

Val Jun 18, 2010 8:01 AM

my mom has green eyes, and my dad has brown eyes,so i got it mixed - hazel eyes.

hazel Jun 15, 2010 4:28 AM

i have very beautiful tentelizing brown eyes

Chelsea May 21, 2010 4:27 PM

Re: I Have Hazel Green Eyes

Jeremy Maztgum,

Not necessarily... both my parents have hazel eyes, yet I have brown eyes, and my sister has green. It's like the hazel split.

Monique Apr 19, 2010 4:44 PM

Eyes

I don't exactly understand my eyes,
they are a really golden brown with almost like green polka dots inside of them, when I wear dark eyeliner or mascara they almost look greenish.

I love my eyes though, I get lot's of compliments. My friend Alley has the prettiest eyes I have ever seen, they are green - emerald green and you could stare at them forever, ugh so prettyyy !

Chelsea Apr 19, 2010 6:43 AM

my eyes will change color

My mother always said when I was a baby,my eyes were lighter and they looked a bit hazel.And now im 10 years old,my eyes are brown.My mom said that my eyes will get lighter when i get older and they will look alittle more hazel.You see,my mom has brown eyes,and my dad has either green or hazel eyes,and my sisters have hazel eyes.SO most likely,my eyes are going to change another color.

Tenshi Apr 15, 2010 7:25 PM

my eyes part2

oh, and also my mom has Green eyes and my dad has Hazel eyes

Tenshi Apr 15, 2010 7:24 PM

I was born with blue eyes but when I was 5 or 6 my eyes turned green and all of last year they were grey and no there dark green again, I don't know if thats normal, but they change colours all the time, even in some pictures I take they show up an aqua blue, brown and even yellow. My sister also actually has yellow-green eyes kinda like cat eyes it's really strange. But I love my eyes no matter what colour they are! hehe ;)

Anonymous Apr 14, 2010 2:35 PM

lourdes ortiz wuz here :))

Jil Apr 13, 2010 2:06 AM

oddity

The entirety of my father's side has dark brown eyes, as well as my mother's. I was born with blue eyes that stayed for a year and then a brown ring appeared and flowered outward, you can still see some blue at the edges..mainly they are green and greyish brown now. Is this strange?

Mia Apr 12, 2010 4:03 PM

brown and green???

My eyes are brown in the midle in the rest are green and at the end of the iris is a black circle is it normal???my parents have black and brown eyes.

Sally Channing Apr 1, 2010 12:18 PM

My Eyes

My eyes are hazel green with flecks of blue in them. Is that weird? If it is, I'm unique!

johana Mar 24, 2010 6:09 PM

eye color

my eyes are wierd cause when i was small i had grey eyes but now i got brown eyes i just dont get it how it happens why it happens and my parents dont even have grey eyes.

Jeremy Maztgum Mar 21, 2010 12:15 AM

I Have Hazel Green Eyes

My Dad Has Little Leopard Shape Brown Eyes And My Mom Has Big Blue Eyes And I Have Normal Size Leopard Shape Hazel Eyes With Long Dark Eye Lashes With A Brown Ring In The Middle And Green In The Outer So That Makes Hazel Green/Brown Eyes Dominant Over All Eye Colors.

Remie Mar 20, 2010 1:36 AM

Hazel

My eyes weird because if you look up close they are mostly a medium green color, but there is a small ring of brown around the pupil, but from farther away, they look gold or yellow.. Also both of my parents have blue eyes, so it's kind of weird that mine are hazel..

Nikki Feb 25, 2010 7:41 PM

Hazel?

I have hazel eyes along with my brother but both of ours are more gray than brown. Around my pupil i have gold lining but my brother has green. My other brother has blue eyes just like my mother and my father has brown eyes. Why such a variation???

Jennifer Feb 12, 2010 10:07 AM

Katherine

The gene for brown eyes is dominant, so if someone has a brown gene plus another color (blue or green), the person will have brown eyes. In order for you to have blue eyes, each of your parents must have one blue gene, and one brown gene for their own eye color (making theirs brown since the brown is dominant). Remember that each parent passes down one gene each to their child, so they each must have passed a blue gene down to you, since, in order to have blue eyes, both genes for your eye color must be blue.

Anna Feb 12, 2010 3:05 AM

Katherine and Jennifer

For both of you, its important to remember that it terms of genetics all it takes is for one person to have a mutation in the genes to affect others down the line. All humans had brown eyes...then POW!~ one day a genetic mutation occurred and made one person have blue eyes.......the same could have occurred in both your cases.
HOWEVER: more likely especially in your case Katherine, you need to look at what your parents PARENTS eye colors where.....it is very possible one grandparent on each side had blue....in which case your eyes would be created from your grandparents genes finally coming together so to speak.

Brent Feb 8, 2010 10:08 AM

Over simplified

In high school they tried to say that one gene controlled eye color, and one gene controlled whether you have attached or detached earlobes. I always pointed to my hazel eyes, and the fact that my right earlobe is detached, and my left is attached. Most didn't appreciate my genes =(

Katherine Feb 4, 2010 11:26 AM

why is it that both my parents have brown eyes and i have blue eyes?

Jennifer Jan 5, 2010 2:55 AM

green vs blue eyes

I don't understand how it could be, that everyone in my family has blue eyes, and yet my sister has green eyes. She is a fraternal twin to my brother, who has blue eyes, as do all of my other brothers and both of our parents.

Hazel Eyes and Genetics

What are Hazel Eyes?

Characteristics of Hazel Eyes

Common Eye Colors

The Genetics Behind Hazel Eyes

Sources

Comments