Неее, давайте свою деревню на весь мир не обобщать, вот, в первое попавшееся исследование тыкнула, Франция, из 1000 участников у 15 был IQ 70+, т.е. нормальный, т.е. 1.5%After the analysis of nearly 1000 clinical files of DS patients at the Jérôme Lejeune Institute, a series of 20 patients with a free and homogeneous T21, aged between 18 and 40 years were enrolled in this study. Patients were classified into two groups: those with a relatively lower IQ (IQ <20 or IQ− four males and one female), and those with a higher one (IQ >70 or IQ+ six males and nine females). The IQ was measured using the Columbia test, a tool validated and largely used in similar settings in France.