Most people are born with limbal rings, and they contribute to the big-eyed, adorable gaze we associate with young children. As you age, your limbal rings will probably start to thin out and become less visible.
This typically happens sometime in your 20s. Some people with darker-colored eyes have bluish limbal rings that can remain quite visible, as well.
The way that your limbal rings look as you age is related to your genetics. Beauty is always, of course, in the eye of the beholder. But some research indicates people with dark, visible limbal rings may be more attractive to others. A study showed that heterosexual women found men who had prominent limbal rings to be more attractive as partners. A research that also found limbal rings were a prominent indicator of whether or not someone was attractive. Researchers theorize that because limbal rings are more prominent during your younger years, potential partners may subconsciously associate a person with limbal rings with youth and health.
Some people find limbal rings very attractive in a partner. Having or developing blue rings around your irises is not usually a cause for concern.
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Here's what you need to…. How common is it for someone to have red hair and blue eyes? What causes these unique traits? And are people with red hair and blue eyes going extinct? There are ways to temporarily change your eye color, but can you change it permanently? Here's what you need to know.
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What are eye color percentages around the world? How is eye color determined? Can eye color change? Health problems that show up in eye color. The takeaway. Read this next. Eye color is directly related to the amount and quality 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 chromosome 15 plays a major role in eye color. 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. At least one polymorphism in this area of the HERC2 gene has been shown to reduce the expression of OCA2 , which leads 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. 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. Several disorders that affect eye color have been described.
Ocular albinism is characterized by severely reduced pigmentation of the iris, which causes very light-colored eyes and significant problems with vision. Another condition called oculocutaneous albinism affects the pigmentation of the skin and hair in addition to the eyes.
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