A

　　Can people change their skin color without suffering like pop king Michael Jackson? Perhaps yes.Scientists have found the gene that determines skin color.

　　The gene comes in two versions, one of which is found in 99 per cent of Europeans.The other is found in 93 t0 100 per cent of Africans, researchers at Pennsylvania State University report in the latest issue of Science.

　　Scientists have changed the color of a dark - striped zebrafish(斑马鱼) to uniform gold by inserting a version of the pigment(色素) gene into a young fish.As with humans, zebrafish skin color is deter-mined

　　by pigment cells，which contain melanin(黑色素).The number,

　　size and darkness of melanin perpigment cell determine skin color.

　　It appears that, like the golden zebrafish, light - skinned Europeans also have a mutation (变异) in the gene for melanin production.This results in less pigrnented skin.

　　However, Keith Cheng, leader of the research team, points out that the mutation is different in hu-man ancl zebrafish genes.

　　Humans acquired dark skin in Africa about l.5 million years ago to protect bodies from ultra - violetrays of the sun. which can cause skin cancer.

　　But when modem humans leave Africa to live in northem latitudes, they need more sunlight on their skin to produce vitamin D. So the related gene changes, according to Cheng.

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