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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 (May 9, 1800 â December 2, 1859) was an American abolitionist who believed armed insurrection was the only way to overthrow the institution of slavery in the United States. Brown first gained attention when he led small groups of volunteers during the Bleeding Kansas crisis of 1856.