Walk down a busy street in most Latin American cities today and you’ll see a palette of skin colors from dark brown to sepia to cream. For 500 years, people have assumed this variation comes from the meeting and mixing of Native Americans, Europeans, and Africans during colonial times and later. People with lighter skin are thought to have more European ancestry, whereas those with darker skin are taken to have more Native American or African ancestry—and are often targeted for discrimination.

Now, a new study of the genes of more than 6000 people from five Latin American countries undercuts the simplistic racial assumptions often made from skin color. An international team discovered a new genetic variant associated with lighter skin found only in Native American and East Asian populations. That means that in Latin America, lighter skin can reflect Native American as well as European ancestry.

“It’s a really important study,” especially because little genetic research has been done on Latin American populations, says human geneticist Sarah Tishkoff of the University of Pennsylvania Perelman School of Medicine. Most work on skin pigmentation genes “has been done on Europeans, where ironically we don’t see a lot of variation,” she says. “One of the last frontiers has been, ‘What about East Asians and Native Americans?’”

Latin America is fertile ground for such studies. People there often have Native American, European, and African ancestors, and because Native American populations are closely related to those from East Asia, researchers can also spot East Asian variants in Latin American genomes. “You get, in one place, the genetic variation from four different continents,” says statistical geneticist Kaustubh Adhikari of University College London.

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