Genetic research reveals the mystery of human skin color evolution
Genetic research reveals the mystery of human skin color evolution October 30, 2017 Source: People's Network Humans have multiple skin tones. Currently, researchers have discovered genes that help to form multiple skin tones. Most people associate Africans with black skin. However, people from different groups in Africa include almost every skin color of the human beings of the earth, from the darkest black of the Dhaka people in the south to the beige of the South African sang. Now, researchers have discovered some new genetic variants that cause various skin tones. The research, published online in the journal Science, tracks the evolution of these genes and how they are carried around the world. Surprisingly, some genetic mutations that cause Europeans to have a lighter skin color also have an ancient African origin. The researchers agreed that our early African ancestors had light-colored skin under thick hair. Sara Tiskov, an evolutionary geneticist at the University of Pennsylvania, said: "If you scrape the hair of a chimpanzee, you can see that its skin color is very shallow. If you have body hair, It does not require the protection of dark skin, so it can be protected from ultraviolet radiation." Until recently, the researchers believed that at some point 2 million years ago, human ancestors shed most of the body hair, and then they quickly evolved dark skin to prevent skin cancer and other harmful effects from ultraviolet radiation. . Later, when humans migrated from Africa to the Far North, they evolved shallower skin to accommodate limited sunlight. In the case of light, the light skin can synthesize more vitamin D. Previously, the study of skin color genes met the above situation. For example, in the past 6,000 years, a "fading gene" associated with light-colored skin called SLC24A5, which is ubiquitous in European populations. However, Tishkov's research team found that SLC24A5, which is ubiquitous in Europe, is also common in East Africa, with half of some human populations in Ethiopia containing SLC24A5. Tiskov said: This genetic variant was produced 30,000 years ago and is likely to be brought by people who migrated from the Middle East to East Africa. However, although many East Africans have this gene, they do not have white skin, probably because the gene is just one of several genes that form skin tones. The team also found two adjacent genes, variants of HERC2 and OCA2, which are associated with European light-colored skin, light-colored eyes and light-colored hair, but they are produced in Africa; the Sans in light-skinned skin These variants are old and common. The research team suggested that these genetic variants appeared in Africa as early as 1 million years ago and later spread to Europeans and Asians. Tishkov said: "In Europe, many genetic variants that cause light-colored skin originate in Africa." The team also used a photometer to measure the reflection coefficient of the skin and studied 2,092 people involved in Ethiopia, Tanzania and Botswana. The team found that the Nile-Saharan herdsmen in East Africa have the deepest skin color, such as the Moorish and Surma; the southern San San people have the lightest skin; there are many shades between the two, such as the Ethiopian Agao Skin tone. This research enriches existing research and weakens old racial concepts. Tiskov said: You can't use human skin to classify humans, just as you can't use other complex features like height to classify. He said: "Africans are rich in diversity, and there is no such thing as 'African races'!" Acrylic Tape,Red Acrylic Tape,Acrylic Packaging Tape,Acrylic Double Sided Tape Kunshan Jieyudeng Intelligent Technology Co., Ltd. , https://www.yuhuanptapes.com