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Scientists find gene that affects skin color
Posted: Friday, December 16, 2005
The merest fragment of one gene plays a major role in the differing skin colors of white and black people, scientists have found, capping an 11-year effort that began with the study of similar color variations in a common pet-store critter, the zebrafish.
The team of 25 geneticists, molecular biologists and anthropologists, most of them from Pennsylvania State University, says the work could have implications for skin cancer treatment, crime-scene analysis, and even cosmetics.
For those bent on altering their skin color, the gene could lead to pharmaceutical products that would be safer than tanning salons or the chemical skin-lightening creams popular in India, said project coordinator Keith C. Cheng, a cancer geneticist at the Penn State College of Medicine in Hershey, Pa.
The research, published today in the journal Science, also challenges a common assumption about when the various races branched off after leaving the scene of their common beginnings in Africa, more than 50,000 years ago. The people who would become Asians and northern Europeans were thought by some to have evolved their light skin together, before migrating their separate ways.
The new research indicates that the two groups developed lighter skin after the separation - giving just a taste of the secrets of history that can be unlocked with the human genome, said Penn State anthropologist Mark Shriver.
Full Article : gazettetimes.com
Fish helps solve puzzle of skin colour
'Golden gene' found in zebra fish same one that whitened skin of early Europeans
Genetic studies have humbled humans more than once. They've told us that we are 98-per-cent chimpanzee, that we share a great deal of our DNA with dogs and that even the fruit fly is a distant cousin.
Now, new research finds that humans and a common aquarium fish also have something in common. U.S. and Canadian scientists have discovered that a gene that lightens the scales of the zebra fish to a golden colour is the same one that helped to whiten the skin of the first Europeans.
A mutated form of this "golden gene," which most people of European descent carry, essentially suppresses the production of melanin, the pigment that gives skin its colour. Africans, East Asians and indigenous Americans carry an original form of the gene that contributes to their darker complexions.
Full Article : theglobeandmail.com
Scientists Find A DNA Change That Accounts for White Skin
Scientists said yesterday that they have discovered a tiny genetic mutation that largely explains the first appearance of white skin in humans tens of thousands of years ago, a finding that helps solve one of biology's most enduring mysteries and illuminates one of humanity's greatest sources of strife.
The work suggests that the skin-whitening mutation occurred by chance in a single individual after the first human exodus from Africa, when all people were brown-skinned. That person's offspring apparently thrived as humans moved northward into what is now Europe, helping to give rise to the lightest of the world's races.
Leaders of the study, at Penn State University, warned against interpreting the finding as a discovery of "the race gene." Race is a vaguely defined biological, social and political concept, they noted, and skin color is only part of what race is -- and is not.
In fact, several scientists said, the new work shows just how small a biological difference is reflected by skin color. The newly found mutation involves a change of just one letter of DNA code out of the 3.1 billion letters in the human genome -- the complete instructions for making a human being.
"It's a major finding in a very sensitive area," said Stephen Oppenheimer, an expert in anthropological genetics at Oxford University, who was not involved in the work. "Almost all the differences used to differentiate populations from around the world really are skin deep."
Full Article : washingtonpost.com
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