posted on 2021-08-19, 09:18authored byAnnette Karmiloff-Smith, Tamara Al-Janabi, Hana D'Souza, Jurgen Groet, Esha Massand, Kin Mok, Carla Startin, Elizabeth Fisher, John Hardy, Dean Nizetic, Victor Tybulewicz, Andre Strydom
In this article, we first present a summary of the general assumptions about Down syndrome (DS) still to be found in the literature. We go on to show how new research has modified these assumptions, pointing to a wide range of individual differences at every level of description. We argue that, in the context of significant increases in DS life expectancy, a focus on individual differences in trisomy 21 at all levels-genetic, cellular, neural, cognitive, behavioral, and environmental-constitutes one of the best approaches for understanding genotype/phenotype relations in DS and for exploring risk and protective factors for Alzheimer's disease in this high-risk population.