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It is named after John Langdon Down, the British doctor who fully described the syndrome in 1866. Some aspects of the condition were described earlier by Jean-Ãtienne Dominique Esquirol in 1838 and Ãdouard SÃ©guin in 1844. In 1957, the genetic cause of Down syndrome, an extra copy of chromosome 21, was discovered.
The Croatoan Mystery. In 1587, the English, led by John White and financed by Sir Walter Raleigh, made their second attempt at setting up a colony on Roanoke Island, which now lies just off the coast of North Carolina in the USA. The colonists disappeared, however, during the Anglo-Spanish War, three years after the last shipment of supplies from England.