The phenomenon of the blue-eyed tribe of Butung Island
We are not at all surprised by blue-eyed Europeans, even if they are sizzling brunettes. What about Southeast Asia, or more specifically Indonesia? We imagine the inhabitants of those regions as dark-skinned and dark-haired, with certainly dark eyes. But it turns out there are exceptions. This is a tribe living on the island of Butung (Buton), located southeast of the large island of Sulawesi. The indigenous people of this place surprise everyone with their bright blue eyes.
We consider this eye color among Indonesians to be a miracle. But scientists explain everything very simply. It turns out that the representatives of the tribe received blue eyes in the same way as the inhabitants of Scandinavia or Central Russia. In any case, blue eyes are to blame for a gene that pundits call OCA2.
Once upon a time, all people on Earth had brown eyes. But then a mutation occurred in the OCA2 gene and a “switch” appeared that could “turn off” this iris color.
But this does not happen in all cases. The mutated gene encodes the so-called P protein, which is involved in the production of melanin. As you know, this pigment gives color to our hair, eyes and skin.
The “switch” significantly reduces the melanin content, but does not completely remove it. Thus, the eye color is “diluted” to blue.
What would happen if OCA2 completely turned off melanin? The consequences of this are well known - this is how albinos are born. The complete absence of melanin makes their eyes very pale and sometimes even red.
Does a gene mutation prevent the islanders from living? Scientists, having studied the inhabitants of Butung, found that hereditary genetic changes do not benefit everyone. Some members of the tribe are deaf or have poor eyesight.
When studying the phenomenon, a small percentage of people with eyes of different colors and with disorders of skin and hair pigmentation were also discovered. This phenomenon was given a scientific name - Waardenburg syndrome. Alas, it was recognized as a genetic disease.