Why do human eyes have different colors?

Eye color is unique and unique like each person's fingerprint. You can see that the people around have the same brown or black eye color as me, but surely the eye color is completely different. You have also seen many people born with blue eyes, but growing brown. Why is there such a difference? Here are the explanations.

What does eye color say?

The eyes are the windows of the soul, but also the door of the genetic gene.The iris , the main part for eye pigmentation, is the part responsible for adjusting the amount of light to the retina by changing the size of the pupil. But why do iris have different colors?

How did eye color form and change?

The most common eye color is brown, the second is blue or gray.

The color of the eye is due to the amount of pigment protein, also called melanin, in the cells of the iris decided. When a child is born, there is almost no melanin in the iris, so there will be blue eyes. From 6–36 months, the cells in the iris begin to produce melanin that will change the color of the eye. If there is too much melanin, the eyes will be brown; less melanin, blue eyes. Most Asian and African children born with brown or black eyes, because melanin has accumulated in the iris. However, sometimes there are some babies born with blue eyes.

Popular and rare eye color

The eye color is not simply green, blue and brown but has many shades.The most common eye color is brown, the second is blue or gray. Rare eye color is green. Very rare eye color is red. These eyes have almost no melanin so the iris will be colorless, but the baby will see red or pink because it is the color of the blood vessels. Some will own two-color eyes because the iris is made up of two different types of genes. This phenomenon is due to a random combination of genes or lesions that cause confusion in the production of melanin. Two-color eyes are rare in humans but are found in dogs, cats and horses.

What determines the concentration of melanin in the iris?

It all depends on the gene. According to previous theories, eye color is determined by a gene. If the father is brown-eyed, his mother is blue-eyed, he will have blue eyes. According to modern science, genes determine a lot about eye color. These cells will regulate the amount of melanin in the iris. In particular, the two main genes that color the eyes are OCA2 and HERC2 . Gene OCA2 determines 3/4 of the eye shades from green to brown. The child's eye color depends on the combination of these two genomes.

Eyes do not constantly produce melanin like hair and skin. Therefore, depending on the degree of concentration of melanin pigment in adipose tissue, the eye color may be brighter or darker.

1. Why do people have two different eye colors?