MAPT and Alzheimer disease: Our binding studies using Tau tracers suggested that the frontal cortex was more affected in terms of Tau binding in DS–AD, compared to LOAD or EOAD [144], which is potentially due to the developmental detriments in frontal cortex organization that have been reported for children with DS, including hypoconnectivity [148], reduced neuronal numbers and brain volume [149], and underdeveloped neuronal migration in the frontal cortex [97,150].