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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.
John Brown, a radical abolitionist attacked the arsenal at Harpers Ferry, VA on October 16, 1859. Hoping to incite and arm a massive slave revolt, Brown and his men entered the arsenal but were soon trapped. After a brief standoff, US Marines stormed Brown's position and captured him and his men.