Whats Melanin? and why we must understand this before we can become a unified humanity by Mikael Shimshon hat is melanin? your body contains melanin, which is responsible for the color of your hair, eyes, and skin. Your skin, hair, and eyes will be darker the more melanin you create. Genetics and the quantity of sun exposure your ancestors received are two factors that affect the amount of melanin in your body. In order to guard against the damaging effects of the sun’s UV radiation, humanity first evolved dark skin in Africa. Some populations that migrated to other continents developed lighter skin to generate vitamin D more efficiently in places with little sunlight. They discovered numerous, grouped around six distinct genes: SLC24A5, MFSD12, DDB1, TMEM138, OCA2, and HERC2. And they demonstrated that in the three countries under study, these variations account for a total of 29% of the diversity in skin tone. That’s a sizable percentage! As a point of perspective, a comparable but much larger study found hundreds of genes that influence height, but that together only explain 16% of the variation observed in large populations. Tishkoff and her team turned to Africa, the place where humans is most physically and genetically diverse, to remedy this imbalance. In Ethiopia, Tanzania, and Botswana, they enlisted 1,570 volunteers from 10 different ethnic groups, and assessed the amount of the black pigment melanin in the skin of their inner arms. In order to determine which variants are linked to a person’s skin tone, the team then examined more
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The genetic variety of these tribes reflects their physical diversity. The first gene to be implicated in human skin color, MC1R, is highly variable in European populations but strikingly constant in African ones. According to Tishkoff, based on this trend, some geneticists have come to the conclusion that because of the high evolutionary pressure for dark skin in Africa, any genetic variations that affected skin color were ruthlessly eliminated by natural selection. Tishkoff asserts, “That’s not accurate,” but this is what occurs when you only look at skin tone in Western nations. “There’s a lot of variation when you look at this African-centered approach.” For instance, variations of the MFSD12 gene, which are connected to darker complexion, are more prevalent in East Africans with darker skin than the San, who have lighter skin. MFSD12 also demonstrates how discovering pigmentation genes can provide fresh information about the fundamental biology of our skin. The gene, which two years ago had no name at all, was connected to vitiligo, a disorder in which people get white patches on dark skin. Tishkoff ’s colleagues demonstrated that the gene regulates the equilibrium between light and dark pigments by eliminating it in fish and mice. A version of the SLC24A5 gene, which is also present in Western European populations, has historically been regarded as being “European” due to its strong correlation with lighter skin.
