How common are gray eyes

The rarest eye color in the world

Home> Guides> The rarest eye color in the worldBrown dominatesThe eye color is a matter of inheritance. The information for this is passed on to their child with the genes of the father and mother. September 2020, updated November 24, 2020

the essentials in brief

  • 90 percent of the world's population has brown eyes
  • Green is the rarest eye color
  • Colored contact lenses are one way to temporarily change the color of your eyes

Almost 90 percent of the world's population has brown eyes. Typical eye colors are also blue, gray and green. Whereby green is the rarest eye color. Only two to four percent of all people have green eyes. There are countless color nuances between the four main colors.

Genes dictate the color of the eyes

Eye color is a matter of inheritance. The information for this is passed on to their child with the genes of the father and mother. If both parents are blue-eyed, they pass on "blue" twice and the child has blue eyes. If the genes are "brown" twice, the child has brown eyes accordingly. It becomes more complicated when different color traits are inherited. If "brown" comes from one parent and "blue" from the other, the child will usually have brown eyes. This is because brown dominates over blue. However, since this child carries both hereditary factors, i.e. brown and blue, from its parents, it can in turn pass both on to its own children. It can happen that children of parents with brown eyes have blue eyes. However, due to the fact that blue is recessive compared to brown, blue eyes are much rarer than brown eyes and are therefore probably perceived as particularly beautiful or frightening in some cultures.

Exceptions are possible

Even if inheritance basically follows certain rules, it happens again and again that something goes wrong when the genes are passed on. Therefore, exceptions cannot be ruled out.

Melanin is involved

It is not just genes that are responsible for eye color, but also Ā«melaninĀ». It determines the pigmentation of the skin, the hair and, of course, the eyes. Depending on how much melanin the cells store, this results in a different color. The more melanin there is, the darker the eyes, skin and hair. A low melanin concentration, on the other hand, makes the eyes appear brighter, blue, green or gray depending on the dosage.

More blue in the north

It is no coincidence that people with blue eyes predominate in the northern hemisphere. Because melanin acts as natural UV protection. In regions with a lot of sun, people therefore mostly have brown eyes and dark skin. Strictly speaking, blue-eyed people are the result of a genetic mutation that has led to the loss of melanin storage in the iris. They are less well protected from the sun.

Baby eyes are often lighter

Unless a baby is born with brown eyes, they can still develop brown eyes. Many babies are born with light eyes. Melanin production is still developing and with it the pigmentation of the iris. Only over time, sometimes several years, does the definitive eye color come to light. This is how light eyes can transform into dark eyes.

Multiple eye colors

There are people in whom both eyes are a different color. In these cases one speaks of "iris heterochromia". These rare cases are based on the fact that pigments are deposited in only one eye or in different numbers. Central heterochromia, however, is more common. The color is different within one eye. For example, the iris has a different colored ring than the rest of the eye. Most of the time, such noticeable color differences are innate. But they can also be the symptom of an illness. Anyone who notices a sudden change in the color of their eyes should therefore be examined.

Change eye color

The color of the eyes cannot be changed any more than our hair or skin structure. Except through surgical interventions, which are very risky. Colored contact lenses, on the other hand, are an interesting way to temporarily change the color of your eyes. But be careful, you should only get this from an optician so as not to endanger your eye health.

Since the eyes reflect light and incident light makes the eye color appear lighter or darker, the eyes always appear slightly different in different lighting conditions. Eye make-up and the color of clothing can also influence the color of the eyes. For example, if you have blue eyes and wear a blue top or scarf, your eyes appear more intense blue.

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