Discover why some blacks have natural blue eyes

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Discover why some blacks have natural blue eyes

In collective consciousnesses, it is thought that blacks do not possess blue eyes, as they usually have dark-colored eyes. But genetics do not care about men. We can mention as black child with known blue eyes the case of Laren Gallaway.
In science
Color of a child’s eyes is specific to his genetic material.
Concretely, how does this happen ?

Parents’ genes play a lot in the color of children’s eyes. The pigmentation of the iris determines the color of the eyes. Eye color usually depends on three brown, green and blue genes. But, other colors exist..

Most babies are born with blue eyes. But, the blue color can be temporarily. Why ? The eyes may change color if the brown melanin pigment develops as they grow. Each parent has two pairs of genes on each chromosome. Its genes in some ways will determine the color of the child’s eyes.

What do scientific studies say?

According to scientists at the University of Copenhagen, a single mutation of 6 – 10,000 years was responsible for all the blue – eyed people living on earth today. Published in the journal Human Genetics, the researchers identified a gene called OCA2 that arose around the northwest coast of the Black Sea in a single individual about 6 to 10,000 years ago..

Other researchers also say that, for example, in America, there are many blacks with European ancestry following colonization. Depending on the amount of European ancestry, it is possible that a black person is blue-eyed.

Warrdenburg syndrome – (genetic diseases of blacks with blue eyes).
Others talk about the Waardenburg syndrome. It is an extremely rare genetic disease that occurs on 1/270 000 births. People with this disease suffer from deafness (uni or bilateral) and have abnormalities of pigmentation. For example, Waardenburg syndrome type I contains a clinical association with at least 2 major criteria or at least one major and 2 minor criteria. The major criteria are: canthi dystopia, pigmentation abnormalities (frontal white lock, eyelashes, eyebrows and white hair, iris heterochromia, two-tone iris, blue sapphire eye color), sensorineural deafness, an evocative family history. (source review of clinical genetics)Minor criteria include: skin pigmentation abnormalities with depigmentation ranges, synophrosis, prominent nose root, hypoplasia of the nose wings, premature whitening of the hair. (source review of clinical genetics)
This disease creates abnormalities in the eye. They are available in three forms:

heterochromia (multiple colors)
bilateral isohypochromia (pale blue eyes)
fundus (reflective) pigmentary alterations (spottiness).

Dutch scientists are currently working on ways to determine the color of adult eyes with DNA analysis. DNA analysis is a new way of understanding how genetics governs eye color. They say that DNA will tell more than 90% if people have blue or brown eyes.
A surprising genetics.
But all blue-eyed blacks do not suffer from Waardenburg’s disease (very rare). Many blue-eyed black children hear and see very well. In my opinion, I think that the color of the eyes and the color of the hair are part of the genetic material and the mystery of life.