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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 Biography. John Brown is a famous figure in the fight over slavery that led up to the American Civil War. Raised in Ohio, Brown moved to Kansas in 1855. The next year, claiming he was an instrument of God, Brown led a raid that killed five pro-slavery men on the banks of the Pottawatomie River. On 16 October 1859, Brown led a raid on the federal armory at Harperâs Ferry in Virginia, with a plan to arm the regionâs slaves and lead them in rebellion.