There are no blue, green or hazel pigments in the eye. This is because these individuals naturally have more melanin in their eyes and skin, compared with non-Hispanic whites. Those who end up with green eyes or hazel eyes develop a little less.īabies of African American, Hispanic and Asian ethnicities usually are born with dark eyes that stay brown throughout life. In the first few years of life, more melanin may accumulate in the iris, causing blue eyes to turn green, hazel or brown.īabies whose eyes turn from blue to brown develop significant amounts of melanin. The reason many white, non-Hispanic babies are born with blue eyes is that they don't have the full amount of melanin present in their irises at birth. The pigment responsible for eye colour is called melanin, which also affects skin colour. The pigmented structure inside the eye that surrounds the pupil and gives eyes their colour is called the iris. This phenomenon has little to do with genetics, but it does help explain where hazel eyes come from. Many white, non-Hispanic babies are born with blue eyes and then develop brown, green or hazel eyes in childhood. For example, we now know it's possible for two blue-eyed parents to have a child with brownĮyes - something the old model of eye colour inheritance would have deemed impossible.Īlso, eye colour can change dramatically in the first few years of life. Recent research has shown that up to 16 genes (not just one or two) may influence eye colour, which makes predicting eye colour much more difficult.ĭue to variations in the interaction and expression of multiple genes, it's hard to say for sure what colour a child's eyes will be based on the colour of his or her parents' eyes. So two parents with blue eyes cannot have a child with brown eyes because neither parent carries the dominant form of the gene for brown eyes.īut it turns out the story is more complicated than that. Most of us were taught in high school science class that we inherit our eye colour from our parents, and that brown eye colour is dominant and blue is recessive. So where does this stunning colour come from? What determines eye colour? One of the reasons it's so hard to describe hazel-coloured eyes is that the hue itself seems to change, depending on what you wear and the type of lighting you are in.Īlso, although hazel eyes appear to contain hues of green, amber and even blue, these colour pigments don't exist in the human eye. Some say it looks like hazelnut, while others call it golden or brownish green. Only about 2% of the world's population has hazel eyes, compared to 9% with green eyes and 45% with brown eyes.For starters, people describe this beautiful eye colour in many different ways. While hazel eyes are not the rarest eye color, they are less common than other colors like blue or brown. Whatever the precise shade, scientists agree that hazel eyes are caused by light-scattering and melanin. Some consider them to be any shade with light brown or gold tones others think they are variation of brown eyes, only with more green or gold in the iris. Opinions vary on what, exactly, constitutes hazel eyes. Finally, the vast majority of the world's population has brown eyes, so any other eye color is going to be relatively rare. This makes them less common than either brown or green eyes. Second, hazel eyes are the result of a combination of low melanin (as with green eyes) and high melanin (as with brown eyes). First, the hazel eye mutation is relatively new, having arisen within the last 6,000-10,000 years. There are a few reasons why hazel eyes are so rare.
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