?

?


Down\'s??????????135???????B??-????

21-?(trisomy2lsyndrome)???;??21???1846Sequin??1866Down???Down\'s?1959Lejeune??21???19601961LejeuneClarke????????:21-???????????????M?0.32~3%?0.56~0.64%
:???3:2
[?] ???????I????I????????????(??????????????)??????20~29????0.62~0.88?30~39?1.06~3.74?40~49
?9.93~62.5;?30?0.1?30~39?1.45 40?12.8??????????????
?????????????????????35???Alzheimer????:??????????????????
[?]
1. :??~??????MelynWhite??110??IQ58?40??IQ??????IQ?????IQ?????? ?????????IQ??
2. ??:...