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variants:
or Down's syndrome
Definition of Down syndrome
: a congenital condition characterized especially by developmental delays, usually mild to moderate impairment in cognitive functioning, short stature, upward slanting eyes, a flattened nasal bridge, broad hands with short fingers, decreased muscle tone, and by trisomy of the human chromosome numbered 21
— called also trisomy 21
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Time Traveler for Down syndrome
The first known use of Down syndrome was in 1961
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