Of all the plants that humanity has turned into crops, none is more puzzling than the sweet potato. Indigenous people of Central and South America grew it on farms for generations, and Europeans discovered it when Christopher Columbus arrived in the Caribbean.

In the 18th century, however, Captain Cook stumbled across sweet potatoes again — over 4,000 miles away, on remote Polynesian islands. European explorers later found them elsewhere in the Pacific, from Hawaii to New Guinea.

The distribution of the plant baffled scientists. How could sweet potatoes arise from a wild ancestor and then wind up scattered across such a wide range? Was it possible that unknown explorers carried it from South America to countless Pacific islands?

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Days after researchers announced that a tiny mummy once rumored to be an alien was actually a human infant, Chilean scientists condemned the new study as unethical and their government began an investigation into grave robbing.

The Chilean National Monuments Council, a government agency, said in an email Tuesday that it had initiated an inquiry into whether the little girl’s remains were illegally exhumed in 2003 and smuggled out of the country. The council has turned over its records to the Public Ministry of Chile in response to the outcry from Chilean researchers. They contended that the grave site was plundered and the mummified skeleton was stolen, violating the country’s laws.

“It’s offensive for the girl, for her family, and for the heritage of Chile,” said Francisca Santana-Sagredo, a biological anthropologist at the University of Antofagasta and the University of Oxford.

In a telephone interview, two authors of the new study, Dr. Garry P. Nolan, an immunologist at Stanford University, and Atul Butte of the University of California, San Francisco, defended the ethics of their research.

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Gregor Mendel discovered fundamental rules of genetics by raising pea plants. He realized that hidden factors — we now know them to be genes — were passed down from parents to offspring.

It wasn’t until the early 1900s, long after Mendel’s death, that doctors discovered that humans weren’t so very different. Some diseases, it turns out, are inherited — they’re Mendelian.

Today, scientists have identified over 7,000 Mendelian diseases, and many are discovered with screenings of children and adults. But a new study suggests that many disorders go undetected.

Continue reading “What’s Behind Many Mystery Ailments? Genetic Mutations, Study Finds” →