The variation in human skin color appeared 900,000 years ago

photo source: Tishkoff lab
at least 900,000 years ago, the color of human skin has been very different. An analysis of genetic variants associated with skin pigmentation in populations in several parts of Africa leads to the above conclusions. At the same time, the latest findings suggest that some particularly dark skin tones evolved relatively recently from genetic variants that control lighter skin tones, suggesting that the racist notion that people with whiter skin are "more advanced" is seriously flawed. The results were published
Journal.
1,500 volunteers with racial and genetic diversity from Nicholas Crawford and Sarah Tishkoff of the University of Pennsylvania. They live in Ethiopia, Tanzania and Botswana. Each agreed to provide DNA samples and have researchers analyze their skin pigmentation.
combined data allowed the team to find eight places in the human genome that were closely related to skin pigmentation levels. Overall, these spots explained about 30 percent differences in skin pigmentation in the volunteers.
for each bit, there is 1 genetic variation associated with whiter skin and 1 mutation associated with darker skin. Seven of the variations associated with whiter skin appeared at least 270,000 years ago, four of them more than 900,000 years ago.
view is that Homo homo homovans appeared in Africa about 300,000 years ago. The latest findings mean that relatively white skin tone variants predate humans and have since been retained in parts of Africa.
some geneticists may be surprised, says Tishkoff, a geneticist. Previous studies of a skin pigmentation gene called MC1R have left many geneticists with the view that darker skin colors - thought to fight UV damage - are a fixed and persistent trait among all people of African descent.
that the presence of MC1R suggests that Africans' black skin is the result of choice and therefore does not have variation. Tishkoff said. However, a review of the past reveals that the history of skin pigmentation in sub-Saharan Africa is much more complex than this, as skin color varies widely on today's continent. Hunter-gatherers in southern Africa, for example, often have light pigmented skin and belong to one of the oldest branches of the Homo sapne family tree. (Source: Science Network Zonghua)